Well I do like sports photography but I don't do it as much as I'd like to. Probably more for like candid portraits and stuff. I'm thinking the 2.8 is better because I do a lot of concerts with bad lighting (local Chicago club gigs). I also usually don't bring my camera out with me unless I PLAN to shoot, so I guess the weight isn't as much of an issue for me personally, its not like I'm gonna be walkin around town every night, dragging this thing around. And to be fair... when you say its 2x the weight, you're talking about 1.7lbs.
I mean I can sweat out 1.7lbs in an afternoon game of basketball... so its really not THAT much, maybe for a lens, but its not much. Maybe I'll start suspending 2lb weights on my wrists for an hour, 5x a week so I can train for shooting with it
