Lines aren't determined by some mythical group of guys running things in Vegas...the initial ones are set by experts and then move according to the action on them. The reason that lines are usually a good thing to look at is that contrary to what people believe, the lines don't move because of public or fan money (As in, a bunch of cornhusker fans betting on Nebraska isn't the reason a line would move in our favor). The main reason they move is that most of the money on these games is placed by extremely informed betting sharps who make their living (or a ton of money aside from a regular job perhaps) betting on sports. Looks like the line has already moved from 4.5 to 5.5 which tells you something I guess.
Don't forget that the game is at UCLA which is essentially 3 points in their favor over what it would be on a neutral field.