I know. Chewy has no animal sales at all so it would be coming from their warehouse or directly from Zoo Med to their warehouse as I'm sure they can offer the deals because they buy in such large bulk that they get massive discounts.
The chances of getting anything in substrate anyways is pretty slim to none but buying from a non reptile supply just stacks it in your favor even more.
That is why i used to go out to Bean Farm directly and pick up my substrate and other stuff from them as they dont sell any reptiles either.