It's called the clinch and is a huge part of the sport. There can be a lot happening in the clinch that casual observers won't necessarily see or appreciate. Some of the all-time greats were masters at working the clinch.
You seem to know your stuff, what are the rules of hugging ? What’s preventing an opponent who knows he is up in points to just do that until the end to not risk any comeback?
Floyd was one of the first persons I thought of that abuses clinching, I remember watching his fight with Pacquiao and it was boring as hell. 12 rounds of nothing.
That fight was such a huge disappointment and was the event that brought my attention to his fighting style.
Yes, I know he's technically within his rights to fight like that. But I am well within my rights to lose respect for a guy who won't face an equal opponent head on and resorts to playing "the game" like a coward.