of the Las Vegas Sports Consultants (if you aren’t familiar with that company, look it up). LVSC was for many years (maybe still is) the largest odds maker. For a few years that company had the only license to sell odds in Las Vegas (casinos could do their own in-house, but no one could sell to anyone else).
Casinos absolutely do try to get even money bet on each side for a game. Maybe not the number of bets. But the money. If they get even money bet on each side, the casino/sports book is guaranteed to make money. That is the case because the sports book takes a percentage of the money won as a commission.