The ads themselves may or may not be useful but the service that's showing you them is probably useful to you, else why are you using it? The company who paid for the ad gets "use" out of showing you the ad, the service gets money from that, and you get a useful service in exchange.
I don't really like ads either but would you really be okay with paying out of pocket to remove every ad you see?
I don't really like ads either but would you really be okay with paying out of pocket to remove every ad you see?