London - the polite city

I was strolling back from Sainsburies at lunchtime having acquired my tuna and sweetcorn sandwich (a snip at £1.30) and came up to a man on crutches walking, as you can imagine, rather gingerly. The path was a bit busy and not very wide, so I moved to one side to let him struggle past. As he was passing me, this suit came from behind him and bumped into one of his crutches causing the bumper to stumble. The able bodied man turned round and said to the man on crutches 'Watch where you are going you twat'.