ATeaM, no one I know is 7' 315lbs... 7' 325lbs, however, is a totally different story.
Besides, I can think of quite a few reasons why people might attack someone that size (street cred, drunken "invincibility", wants to test themselves, etc.)... but, I'm told, that isn't the point of martial arts, now is it? People can want to learn to do martial arts and how to fight, for other reasons than wanting to or expecting to fight.
Coronach, I end up watching the Lakers fairly regularly as Kobe's my brother's favorite player. While he might not be a "lumbering giant", he
is slow in a martial arts/dexterity kinda way... put another way, we don't expect Shaq's next film to star opposite Jet Li where Shaq is described as having "Fists of Lightning".