Agree with all of that, I've been to a ton of rugby matches (coincidentally, most recently Saints vs Leicester) and they're really friendly places to be. Fans sit next to fans of opponents, share jokes, chat and everything like that but it's all with a smile on your face. About the police, I can't ever recall seeing many. Obviously there's some (there's thousands of people at every match, obviously things happen occasionally) but they're not visible at all.