People were saying today that the Spurs +1.5 is a trap line. OK, they were right as the Spurs got blown out of the water. But it made sense that the Spurs might lose despite the line, because Tony Parker was out, one of their key players. Plus, Grizzlies have had a good record lately and are decent at home, plus the revenge factor.
So here's my question - how exactly does Vegas know that they can set a line as a trap? Do they know more than all of us do? I can't imagine the bookies sitting there sayin, "Hey, tomorrow, lets put a line much lower than it should be at! Let's get those suckers!"
I feel like if the Spurs line was today was set at -5, people would have said that that line is about right. But since it was +1.5, the public just because of this suddenly believes that the Grizzlies can win for no reason other than the line being set so close. People just like to associate close lines with the word "TRAP".
IMO bookies would rather see a 50%/50% betting spread to guarantee a juice profit every night rather than to risk losing money on setting a trap line that will be split 99%/1% to the trap favorite.