[deafpolygon]

Gambling as an industry is held up by (I don't remember exact numbers) something like 3-5% of gamblers that provide nearly 50% of the revenue.

I imagine it's similar here.

[zerocrates]

I don't have specific numbers, but that's definitely how a certain type of really successful mobile game works: they're nominally very cheap (typically free) but offer lots of ways for the diehards to pay: skipping past grinds, bonuses/enhancements, more pulls or better odds on random chance elements, piles of expensive optional cosmetic items, and so on.