The vast majority of clubs will provide a warm welcome and even those where owners or supporters hold views that might be viewed as gammony do a lot of good stuff within their local community and supporting charities.
I’ve never been to a game and really felt as though a club’s supporters have, as a collective, been overly twatty. Many clubs, if not all, have a minority who overstep the mark on occasion - even Dulwich and definitely the new Clapton - yet no-one actively identifies with the right in the way that some do with the left.