Either use a different command maybe or just tag it below the normal appraise message (envisioning kind of like the @review-cloth messages).
I often find that items will have a neutral @describe, but have very specific @worn messages for the person who used to wear the item - which requires the item to be retailored.
I think that can be used as a baseline for how much less "fancy" you should expect markets to be. Which isn't me saying I think you should be -unable- to check coverage in markets, because you should, but perhaps it would be best done in a simple and crude, but IC, message, rather than something like printing the @check.
Anything at all can be in a market - fancy items or shabby ones. Not being able to know what it will look like when worn is really not, in my opinion, something that should be explained away ICly, it's something that should be fixed (per the original idea).
It doesn't have to be an OOC @ command. It could just be an update to what the IC 'appraise' does.
The @worn message is a bit weirder because... again, there is an IC feature meant to provide this... at appropriate venues. Specifically, seeing the item -worn-. The market doesn't have that, so it's understandable to me that you would get the item's -description- when looked at in your hands, instead.
I still absolutely agree that coverage should be divulged, though.
