I'll copy and paste what I replied with in e-mail to a few people who complained...
The no role playing server rule was actually NOT instated by me, however, I support it 100%. The master server is for people intending to play SRB2 online. SRB2 is an action-platformer with first person shooter gametypes. It is not a role playing game. If some newbie joins the master server and is looking for a game, they should find a real game of SRB2, not a chat room, which is essentially what a role playing server is. You wouldn't want someone advertising their chat room on your website, so why should we let you advertise yours on our network? We aren't going to stop you from making role playing servers, though, and I honestly have no problem with you running them. We simply ask that you do not advertise them on the master server, as a large percentage of people do not want to see servers that you'll be banned from if you play the game the way it was intended to be played.
You can still easily set up games without the master server. Simply get the IP address of the person hosting, and join using the "join with IP" option, or use the console command "CONNECT <ip address>". You can also use the command line parameter "-connect <ip address>" if you're running from a command prompt.
This is not intended to be repressive or otherwise absurd, but the person who owns the master server is allowed to set up his own rules, and we agree with the rules he has set up. If you do not like the rules we have, you are free to not advertise your servers, or use the SVN to set up your own master server with role playing servers allowed.