Paying a fair price for something isn't 'charity'.
No, it isn't, but paying for something that you don't need for a price you're not otherwise willing to pay, is charity.
I see often people talking about products they'll buy to 'support' either their LFGS or publisher xyz, even though they don't actually 'use' either the gaming support at the LFGS or even read/use the product they bought. I consider that charity.
If you buy book xyz to read or game with, then you pay whatever price they set it at and you're willing to pay for it. And let's not forget that what is 'fair' is not clear, not even to the publisher. As an example, how often did we pick up RPG books from the bargain bin? While it was previously $40, it's now $10, because no one wanted to buy it at $40, not at $30, not at $20, but at $10, now you pick it up. In the same way, I paid $60 for three Paizo PDFs, and a couple of months later I got a Humble Bundle for Paizo products for $29 for dozens of products, including the three PDFs I bought at the MSRP PDF price.
'Fair' is a moving target, which relates to income of the purchaser and how often it will be used vs. what it costs to make by the seller and how many they expect to sell. But the reality of the market is that sellers sell at the price the market will bear, not what is 'fair'. Because if the 'fair' price is too high, they won't sell anything and they're stuck with product they can't move, too low and they're leaving money on the table in profits. In a normal market products with a too high a price just don't get made, in the pnp RPG market people are willing to work for peanuts, so it's extremely skewed in the first place.
Imho if the price of a product isn't 'fair', the publisher shouldn't be making it in the first place. If the money a writer/illustrator makes isn't 'fair' they shouldn't be working in the pnp RPG industry at all. But if you're willing to sell it to me for peanuts, who am I to say no? I ain't no saint!
And how would a
saint price a product? What it costs to make (seller) or how much it is used (user)? Because a D&D PHB (or other system equivalent) would have a HUGE amount of value to someone that plays D&D weekly for the next decade, it would essentially be priceless. Compare that to a one shot adventure that you play one session, what about an adventure, or a campaign? A hammer has a different value to someone that uses it only to hammer in a nail to hang a picture vs. someone who builds their entire home with it. And what about someone that uses it daily for work...
Markets change, due to inflation, tariffs, costs, distribution shenanigans, etc. Even the buying behaviour of your customers will change due to external factors, ranging from technology advances (tablets and e-readers), to pandemics where people start playing online and afterward keep playing online. It wouldn't surprise me at ALL if the higher price of the Paizo books is due to projected sales prices of the physical books being worse then back in 2017. I know it's worse for SF2e then it's for PF2e Remastered from two years ago, which in turn is worse then the D&D 5e physical sales. While some still
prefer physical books, some
need physical books because for some reason they can't comfortably read books on a digital medium. But over time more and more people will prefer digital over physical, making physcial products even more expensive...