If 50k gold was the cost of a new heart for Karlach I would feel completely different about it.
I'd really like a game where eventually the shopkeeper tells you: "Look, you've already sold me 10 of these +1 magic swords. We've got only 8 capable warriors of fighting age in this village, and none of them have the kind of money to buy these swords. I'm afraid I can't justify buying even more from you."
Skyrim kinda-sorta did this, but the campaign didn't have any hard limits of "world ends in X days" to stop people from just waiting for an economic reset, and there were some other ways to glitch things.
I think it would be interesting to see some actual supply and demand: if you're flooding the market with crap you looted from goblins, at some point they become worthless. Even +1 magic swords can become worthless if you sell enough of them.
So that's what I'd suggest for consumables. Give a limited number so the player can't hoard and aren't too powerful, but make getting more of them easy and frequent.
However, one nice thing with Doom is its commitment to the "fps chess" system. Chainsaw ammo might be scarce but the decision to use it is intuitive and requires no second thoughts. With BG3 every opportunity to use a limited item tries to awaken my latent save scummer and it feels like you can never make a good decision without first knowing how the story will play out.
I think WoW's move also kinda works. It's a question of economics and you should mostly always be using them.