Imo a line of 5 1/2 in a game like this by its nature will bring in lots of dog players.
What I mean is when someone sees a line like this, many will conclude-"Wow just think if Clemson wins, or just loses by 3 or 4,( which are both important
numbers when it comes to betting on football), I win."
On the other hand, they don't look enough at the other side of the coin, namely that good teams can and do when by a touchdown or more.
I have a hunch if the line had been a pick or even three, you would have seen a lot more folks on LSU.