Hello Jeff
Re: your question
What is the advantage to laying odds that pay less than even money?
Good question. There's no doubt that Pass/Come bets with positive Odds are a bettor benefit. So why bet More to get Less on the Don't Side? Answer: because those bets come in and pay out. Thats a big reason. Its only a good bet if it comes in.
All of you that play the MCG simulation or play on a live table know that the shooter Sevens Out more than makes Points, over time. Sure you will get a hot shooter make 3,4,5 points in a row and then its back to Mostly Seven Outs.
This is typical:

Being that there is an 18% DIS-advantage during the Come Out roll, suffering the many Sevens and occasional Elevens, most Dark Side bettors will start with a modest Dont Pass and then take Odds. Note that on a standard Las Vegas 3,4,5X Odds table, how the math works is that you can bet up to 6X in Odds. A $10 Dont Pass bet can have up to $60 Odds on ALL points. This has to do with the actual Winning payout on the Dont side.
Recall the bottom line of this Standard Odds chart:
