I have not run into any app like that so far. Can you provide an example?
If it is because I just bought it and it get a new paid update I would look at the version history and see when it last was a paid update. you can be unlucky buy in the end of a cycle, but thats the case with everything you buy.
What others have said. Or, is this in regards to the 32 bit app support dropped in iOS 11? Or developer abandoned the app, and in turn, Apple pulled from the app store?
This is such a broad and over-general statement. You might as well say "how do you feel about restaurants that serve small portions?" Uhh... not great. I skip them an go to different restaurants.