I think you'll find that the majority of British people who hate Khan are the ones who hate him for non-boxing reasons/ hate asians in general: i.e. EDL/ BNP supporting chav thugs, usually fuelled by jealousy. The other section of British fans that dislike him, do so for boxing reasons... just like why one would dislike David Haye, for example.
I like Khan now he has been refined by Roach. Obviously Roach will keep him away from true danger men, as Roach's reputation is all that matters. Wish he wasn't being managed by complete fools however. Despite becoming a better fighter, his career and fame are backtracking somewhat.