This is like complaining Jersey Shore adds nothing of value to people's lives. Sure, it doesn't, but it's not supposed to. It's entertainment. Just because people are easily entertained and advertisers will pay for those eyeballs, doesn't mean it's not a financially viable business.
Some apps solve problems and are useful. Some apps entertain (solving a different problem - boredom). Confusing the two purposes leads to posts like these.
(For the record, I completely agree that there are a lot of useless apps out there, but how is that different from there being a ton of useless TV shows, movies and video games out there? If you don't want to contribute to that because you think it's a poor use of time, then don't, but it doesn't mean that there's not a market for it and that there isn't money to be made there).