Not lovin it

I just want to cast my amazon prime video. I download this app and immediately it wants money for all kinds of options that i dont even know what they are. Why cant i just start my video, hit a cast icon and start watching it on my tv??!!

Sagolf100 about Video & TV Cast for Chromecast: Best Browser to watch and stream free movies, webvideos, sports, live tv and camera roll videos, v1.8