I noticed the same thing. It's ridiculous. Geforce Experience doesn't do anything I care about except auto-update drivers. Why do I need to log in for that?
The "experience" app is just superfluous bullshit.
Anyway, everything is shit ;)
It's especially nice compared to normal H.264, and has the option of light compression with nominal CPU usage if you don't like large lossless files. It outputs normal MP4/H.264 files that I can then work with in Linux (as opposed to say Fraps) but uses the fact your GPU is already rendering the scene to then output it in H.264.