The more you use it, the more it knows your type, the more it recommends them, then it dangles out more possibilities that are just beyond reach but could be accessible if you just throw money at it.

The prospect of matching with someone you find very desirable keeps you swiping, making you more likely to do it in the future.

I'm not sure if this is necessarily unethical, but it is clearly an example of a knowledge-based power imbalance. Because I am quite sure the majority of Tinder users are unaware of all the machinations behind the curtains.