Sorry for the double post but I have done a lot of thinking about the factors behind house edges. As an economist I find these things interesting.
WHY MACAU HOUSE EDGES ARE LOWER THAN VEGAS: POSSIBLE FACTORS
(note: these are all theories)
1) Labor costs. A Macanese dealer costs less than an American dealer.
2) Shoe vs. CSM. Macau prevents Advantage Play and thus they can rely on a more consistent flow of income from the game.
3) Competition is quite intense since a monopoly (Stanley Ho's SJM) recently lost its priveliges and thus other companies are aggressively carving out market share. It seems fortuitous to note that the BJ house edge at all SJM casinos apart from the Lisboa (and possibly the Grand Lisboa) is higher than the house edges of any of the competitors (see
http://www.wizardofmacau.com).
4) Blackjack is not the big game in Macau. Baccarat is. And Baccarat has a house edge of at least 1% on the "banker" hand (the lowest house edge in the game). Baccarat provides a larger and more consistent stream of income than Blackjack.
5) Macau's clientelle is less 'cashed up' than Vegas's (note: this does not stop the Sands casinos from demanding HKD$200 table minimums!!!).
6) Macau is much more gambling-focussed wheras Vegas has a more diverse focus. Thus, the marginal benefit gained by the casino from each gambler must be higher since the average Vegas gambler probably gambles less religiously than the average Macau gambler (ceteris paribus).