How!?
That's...Wow. That's not my experience at all.
I've literally never seen a frigate that wasn't a Tempest or Hyperion cost more than 20-something supplies to recover.
I've even recovered Tempests and Hyperions that cost less than that.
Seriously, I'm well curious as to why that's as expensive to recover as it's showing...
Vanguard is 6 DP, so it costs 6 supplies to recover. It uses 10% CR for deployment. Therefore, 10% CR costs 6 supplies to recover. As a destroyed ship it starts at 0 CR, and therefore takes 60 supplies to recover 100%. Assumedly the crew training skill is slightly strained, pushing down maximum CR to 97-99 % would explain the 59 supplies requirement.
Alternatively, a Tempest has a CR per deployment of 20%, and a DP of 8. This means to get it to 100% CR it would take 40 supplies. Which is still less than the vanguard.
Essentially the Vanguard being destroyed means it essentially as the same wear as ten back-to-back battles, compared to a Tempest's five or a Hyperion's two and a half and takes correspondingly more supplies to recover.
CR is detailed
here.