The fair pricing is what the market will tolerate. I’m not saying it’s 100% “justified”; even the dev understands that he needs to tweak it for other regions. But the value add is from the superiority of the app experience, which right now is much better than anything else available (for me; of course this is all subjective). In the future, perhaps other apps will achieve parity with Sync, at which time market forces will cause the developer to course correct on pricing.
I’ll also add that I purchased Sync for Reddit (Pro) for USD$2 nine years ago. If I get nine years out of Sync for Lemmy that’s a bargain at even 10 times the price (which is the current offering).
No, it’s a one time payment just to remove ads.