Any particular reason why? The only thing I can think of is the paid mods thing (where steam takes a good portion of the cut), but that's out as far as I know.
I think the "anything you post on the workshop belong to us" segment of the EULA is a pretty big reason. An I too would stop modding if the workshop was implemented.
This is grossly misrepresenting what the actual terms of the license are. I was curious so I looked it up. Copy-paste of the relevant section at
http://store.steampowered.com/subscriber_agreement/ (along with my English translations):
Spoiler
6. USER GENERATED CONTENT
A. General Provisions
"User Generated Content" means any content you make available to other users through your use of multi-user features of Steam, or to Valve or its affiliates through your use of the Content and Services or otherwise.
You grant Valve and its affiliates the worldwide, non-exclusive, right to use, reproduce, modify, create derivative works from, distribute, transmit, transcode, translate, broadcast, and otherwise communicate, and publicly display and publicly perform, your User Generated Content, and derivative works of your User Generated Content, in connection with the operation and promotion of the Steam site. This license is granted to Valve for the entire duration of the intellectual property rights and may be terminated if Valve is in breach of the license and has not cured such breach within fourteen (14) days from receiving notice from you sent to the attention of the Valve Legal Department at the applicable Valve address noted on this Privacy Policy page. The termination of said license does not affect the rights of any sub-licensees pursuant to any sub-license granted by Valve prior to termination of the license. Valve is the sole owner of the derivative works created by Valve from your Content, and is therefore entitled to grant licenses on these derivative works. If you use Valve cloud storage, you grant us a license to store your information as part of that service. Valve may place limits on the amount of storage you may use.
If you provide Valve with any feedback or suggestions about Steam, the Content and Services, or any Valve products or services, Valve is free to use the feedback or suggestions however it chooses, without any obligation to account to you.
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Any content you make available, we may modify, display, and distribute in connection with operation/promotion of Steam. This is a catch-all clause that allows Valve to use your content for advertising and promotional materials if they want to.
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Spoiler
B. Content Uploaded to the Steam Workshop
Some games or applications available on Steam ("Workshop-Enabled Apps") allow you to create User Generated Content based on or using the Workshop-Enabled App, and to submit that User Generated Content (a “Workshop Contribution”) to one or more Steam Workshop web pages. Workshop Contributions can be viewed by the Steam community, and for some categories of Workshop Contributions users may be able to interact with, download or purchase the Workshop Contribution. In some cases, Workshop Contributions may be considered for incorporation by Valve or a third-party developer into a game or into a Subscription Marketplace.
You understand and agree that Valve is not obligated to use, distribute, or continue to distribute copies of any Workshop Contribution and reserves the right, but not the obligation, to restrict or remove Workshop Contributions for any reason.
Specific Workshop-Enabled Apps or Workshop web pages may contain special terms (“App-Specific Terms”) that supplement or change the terms set out in this Section. In particular, where Workshop Contributions are distributed for a fee, App-Specific Terms will address how revenue may be shared. Unless otherwise specified in App-Specific Terms (if any), the following general rules apply to Workshop Contributions.
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Blah, blah... we can remove your stuff from the workshop if we want. We may release your mods as "paid mods" if we so choose, but how revenue is split is dependent on the developer (Alex).
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Spoiler
Workshop Contributions are Subscriptions, and therefore you agree that any Subscriber receiving distribution of your Workshop Contribution will have the same rights to use your Workshop Contribution (and will be subject to the same restrictions) as are set out in this Agreement for any other Subscriptions.
Notwithstanding the license described in Section 6.A., Valve will only have the right to modify or create derivative works from your Workshop Contribution in the following cases: (a) Valve may make modifications necessary to make your Contribution compatible with Steam and the Workshop functionality or user interface, and (b) Valve or the applicable developer may make modifications to Workshop Contributions that are accepted for in-Application distribution as it deems necessary or desirable to enhance gameplay.
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We only have the right to make changes to your content in two scenarios: what you uploaded isn't actually compatible with the workshop OR if you mod is really, really broken in terms of gameplay. I can only see Valve using the second part of the license to touch things up if they were going to do paid mods.
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Spoiler
You may, in your sole discretion, choose to remove a Workshop Contribution from the applicable Workshop pages. If you do so, Valve will no longer have the right to use, distribute, transmit, communicate, publicly display or publicly perform the Workshop Contribution, except that (a) Valve may continue to exercise these rights for any Workshop Contribution that is accepted for distribution in-game or distributed in a manner that allows it to be used in-game, and (b) your removal will not affect the rights of any Subscriber who has already obtained access to a copy of the Workshop Contribution.
Except where otherwise provided in App-Specific Terms, you agree that Valve’s consideration of your Workshop Contribution is your full compensation, and you are not entitled to any other rights or compensation in connection with the rights granted to Valve and to other Subscribers.
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If you remove your contribution from the workshop, we will remove the contribution from the workshop, but not delete it from users' computers if they've already downloaded it (because that would be INSANE).
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Literally none of the EULA is scary whatsoever. The very worst case scenario that these EULA terms allow is Valve arbitrarily deciding that the mods are now for-profit and they start sending modders royalty checks (unlikely to happen, unless Alex demanded paid mods). Bring on Steam Workshop.
