They also limit large bets to around $30,000 at most places. They don't want a single huge bet at a certain limit to swing the numbers hard. Imagine if 100 of us bet $1000 each. And then one guy comes in and bets $100,000. He now has bet half of the money they've take in, and the house will have a hard time balancing the books on that one.
In the end, just understand that when betting on fights, you are betting based on public perception. If you think you know better than the general betting public (including the very-well informed big money), then you place your bets when you see odds that satisfy you. A fighter is at -200 when you believe it should be closer to -350? Make that bet, even if you don't stand to gain very much. It's net positive if you're right about the math.
Likewise in the other direction. The line shows +600 on an underdog and you think it will be a much closer fight, or the guy has a punchers chance that shouldn't be taken lightly? Maybe you think it's more accurately a +300. You should put your money down, knowing that you are more likely than not to lose it, just because if it does hit, it pays much better than your expected odds.
