Its not the amount being bet its about who is betting. At least for the major team sports. Vegas knows they will always beat the average degenerate in the long run and do not react much to them, even if that means they have individual games that are massive cash liabilities. The ones they actually care about are the quantitatives. Action from them is what moves the lines. This is why you see lines move toward a side getting <35% of the money regularly. They are so reactionary to this certain group of individuals that at these math folk often place preliminary bets to move the line a point in the direction they want and then they hammer it. Which is why line movement in the last 48-72 tells you a lot more than earlly line movement
Getting even money on both sides is a strange widely perpetuated myth. There is a massive “they just want to encourage people to bet team x” echochamber. Usually regarding lower tier/smaller market teams. Which sounds good but when you think about it from a probability pov, it doesnt make sense. Vegas would absolutely love you to place your bets based on which team is the bigger name or which is the bigger market.
Vegas makes money protecting themselves from the small group of sharps, and from the vig. The rest, with a large sample size (its very large) over a long enough period of time, because of variance and the neccessary break even win point of 52.5% for gamblers, math says they will win.
Utah @ 
Colorado 
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