As I said, 'many team sports' above that. The next point was just about soccer, not implying rugby is any better.
I wonder if a factor in it is that a team as a whole generally doesn't get tarnished for the unsporting actions of one player (unless it's routine) so the penalty (publicity/sanction) for doing it is usually less than it would be in a sport like tennis, triathlon or golf.
I mean, really, who would argue that it is better for a soccer match to be played where major rules are ignored simply because the ref was too slow, looking at the wrong thing etc? Or, worse yet, leaving it up to the integrity of the players which, in overall sporting terms, soccer players seem too often to be at the very bottom of the heap (diving, faking injuries included).