You get NastyCredits. They are basically worthless at this time, but we are going to work to provide them some value at some point in the distant future. My hope is that they grow into a tool that can be used as a sort of Nasty line of credit and are eventually purchased for utility, entertainment, & speculation.
You would have to get an official response from nonnakip for your second question, but one of my requests was that no identifying information be required in the signature so you shouldn't feel opposed to signing your address. You should also get in the habit of owning your private keys if you do not already.
However, looking at https://nastyfans.org/members.csv any idea why the member count went from 307 to 614 overnight this month?