The price for Kagi is not really in the class of "luxury" at $10 per month. It's peanuts really. In exchange you have the best search engine in the world.
If you could upgrade an economy flight ticket to first class for $10, that would be a bargain. If you could buy the best bottle of wine in the world for just $10 more than your average bottle of wine, that would be a bargain. Kagi is the best search engine in the world, that's why I pay for it.