Boost for Lemmy

Whilst developers can ban specific ads, they can't really vet them beforehand. I think you can opt out of political ads (or maybe could at one point), but technically the ad you see is just for another app.

As an alternative solution to the ones already posed by others, you can use "Google Opinion Rewards" to get enough play store credit to buy the app. Every so often it'll just ask if you googled "Ninja Coffee Bar" (literally), and give you 10-25 cents for answering, and typically a good bit more for any follow-up questions ("How helpful were the results", etc).