There’s a lot of talk going around about casino competition to allow higher limits on the "odds" bet at craps. The so-called 2 times or 10 times or 100 times or whatever "x" is merely a "times" bet as a multiple of one’s original line wager (Pass or Don’t).
Originally, the fearless Binion’s Horseshoe (downtown Vegas), with a huge "fade" bankroll, was the first to advertise 100 x odds bets. Along came other players such as the Frontier and Stratosphere, who were quick to jump on the odds bandwagon.
The "free" or "true" odds bet was first allowed about 75 years ago as an accommodation to high rollers. There’s no marked spot on the craps layout, so it’s an acknowledged bet by the craps crew, overseen by the boxman and pit supervisors. Its true odds status is because the wager is paid off at "true" odds as its probability of occurrence, and is based on point numbers (after come-out).
True take odds against any point being successful on the Do Pass line are:
|4 or 10||2-1||1-2|
|5 or 9||3-2||2-3|
|6 or 8||6-5||5-6|
True lay odds are the opposite on the Don’t Pass line. There’s no house vigorish on the odds bet. Technically, it’s a separate side proposition bet. The house couldn’t care less, as it’s a break-even affair to them over the long haul.
After a point is established, a player can make odds bets, or even take them off, at any time before decision. In fact, he can do that as well with Don’t Pass line bets. He can also bet on the Pass line after the point is made ”” only, bets cannot be taken off the Pass line before decision.
Since about 85 percent of all crap table bets seem to be made on the Pass line, that’s where the house wants to take a shot, for 1.414 percent vig. So, to qualify for an odds bet as a separate proposition, its maximum bet size is controlled by the size of the original line wager. That is whether the odds bet is 1 x, 2 x, 10 x, or 100 x, the maximum size is determined by the multiple allowed, but it can be less.
Thus, if you had $10 working on the Pass line, at 100 x, you could place up to a $1,000 wager as an odds bet on the space below the Pass line. If your point was 4 and you made it, you could win $10 on your line bet and $2,000 on your odds bet. If you laid the maximum odds on a Don’t 4, for a $10 original wager, you’d place $2,000 behind the line to win $1,000, etc.
If you have subsequent intermediate bets via the Come/Don’t Come line, these are moved by the dealer to the number boxes. You must hand the dealer appropriate chips to "press" an odds bet.
The house isn’t stupid. The reason they spin their wheels on the odds bet is to encourage and give incentive to the player to make larger line bets (at vig) to qualify for larger odds bets.
While some players convince themselves they are reducing their vigorish by making odds bets, it’s a delusion as far as the house is concerned, as they couldn’t care less. They concentrate on taking a shot at your line bet.
The house, however, does place itself at some risk. Having some shooter with a long duke throwing numbers (sans 7), it may take some time to recover. A big backup bankroll is a necessity. Also, they must use constant vigilance to keep from being "past posted." That’s where a cheating player will surreptitiously drop some chips behind the line if he sees the point is made. Dealer collusion helps.
Also, you need sharp dealers. Even though the maximum odds are 100 x, say a player only bet 37 x the odds and the point was a winning 6, which would pay 6/5 odds. This could entail tricky chip-counting arithmetic.
Let’s look at it this way. Suppose you’re in a bar and flipping a coin at true even odds for $1 per toss. Another guy sides in and says he’ll flip you for $10, still another says he’ll go for $100, etc. That’s why I think contemptuously about all this odds-war folderol.