In gambling, bookmakers = the market. Just like a lot of demand (unbalanced amount of money) buying up a stock pushes up the price, the same will cause bookmakers to adjust their lines.

It's very, very hard to make a model that outperforms bookmakers in the long run. If you find some sort of inefficiency in the betting market, maybe. But it turns out that most often the betting market is inefficient at the points where casual betters outnumber the "sharps," which tends to be the points at which the bookmakers have the highest juice on their odds, so you're not likely to come out ahead anyway.

do you happen to know where one could find data on this? Not just bookmakers' odds, but volume of bets? This would make for interesting research

Betfair has an API. This can be used to return the odds and volumes matched for all sports on their Exchange platform.

https://developer.betfair.com/