The first few tents in the officially designated grimoire section of the Resource Center had resorted to selling other training materials alongside their grimoires since their tents looked so empty otherwise. Having to sort through all the miscellaneous rubbish made it more difficult to spot the grimoires. It seemed to be a tactic intentionally employed by the sellers.
The peddlers could get people interested in their other goods by making people stop and look through their items in search of a grimoire. It might work on people who were actually interested in things like 'The Basics of the Elements by Rando.'
Unfortunately for the sellers, Toz and the cats only wanted to buy stuff that piqued their interest or would help them get better at magic. And they were already quite knowledgeable about the basics of their attributes, maybe not so much about other attributes. But they didn't need to know in-depth how an element worked for them to beat it or its user.