There was no interest in it. Not from the casinos OR from the customers who were betting their money.

What's interesting here is that this was, at least initially, the motivation for SatoshiDice: that you could prove their lottery was fair. It's exploded in popularity far more than that seems to warrant. I've never used it, so I don't know how convenient it is, but if it's as convenient as it sounds (no need to register accounts or log in, just send bitcoins to addresses, AFAIK), that's more evidence that convenience is Really Important.