There's betting in the middle and betting on the rail. Two different things.
Betting in the middle is the bet between the combatants including their backers. Side bets between non combatants is betting on the rail or side betting. Saying "in the middle" makes it clear how much money is at stake. It's a total of 49K in the middle. Anyone know what was on the rail?
Years ago, we'd say "on the lamp." People normally would get confused if someone would say, "they were playing for 20 large" without clarifying whether that was in the middle or 20 a piece, crazy stories then escalated. The next guy could say, yeah, it was 40k (thinking that the original person meant 20k a piece). Without clarifying, the next person migh say, "yeah I heard it was 40k a piece...." So, 20k in the middle could get blown to an 80k legend very quickly.
Backers in the middle normally have a pre-determined split of the winnings with their horse. If not, serious bad taste can follow. I assume that's pretty consistant across the world.
For rail betters, normally a jelly roll to the winner would be nice, but sometimes that doesn't happen. Internet betters for example aren't normally going to Paypal the winner some jelly. Maybe they should.
Fred