Why do they censor the subtitles
 

If it is ok for us to hear them swear. Then why cant we read them swear?

haha that never occurred to me, yeah it does seem pretty silly.

Are deaf people more prudish that people with the ability to hear?

I'm not so sure, I think reading "*********G" does look far more harsh than it actually sounds, if you can hear it then there isn't really a problem about it being blocked out, I've no problems with them blocking it