I've done this in my games as well. I've also had rules where spells over a certain level could not just be bought. But I feels, especially at higher levels, like I'm just putting extra restrictions on one class.
One campaign I've wanted to run is a campaign world where arcane magic is banned and for the most part lost. The known world is basically ruled by theocracies. The party would be part of a hidden group trying to rediscover lost arcane magic. Most of the adventures would be tied to seeking spell components, magic items, and spell scrolls/books.
Two things are keeping me from running it. The first is just time. I really don't have the time for prepping a homebrew campaign in the way I would like. But the second is that I don't think my current group of players would be up for it and I certainly don't have the time to run two campaigns.
The problems with this campaign idea, I think, for many players include:
- Not wanting to track and rely on spell components.
- Players playing wizards not wanting to be limited to what spells they can select when leveling up
- Non-wizard players not wanting to be seen as second-fiddles and support characters for the wizards
I think that the third point is easily addressed with good plot lines and back stories and ensuring that there are rewards for all involved. The first two require a specific kind of player who would enjoy the story ramifications of those limitations.