No doubt that Casino will bring certain undesirable social effect. I will not doubt that.
Nobody can say for sure that a casino will a huge success but until this point of the century, it does seems to be the most viable option.
As the point that other tourist business will be affect, I do doubt it is the case. Tourist attraction like that zoo, birdpark, sentosa defintely depends on local visitor for a huge %. Just ask how many oversea tourist how they felt abt sentosa & zoo, none that I knew say we're world class and even consider visiting it again. Not even the underwater world. We can see that sentosa knew that because there are some shift in their market strategic, they are creating a lifestyle imgae tragetting at locals.
As for foreigner spendings, many rich and super rich business, royaties and celebrites around the region whom spent good $$ in singapore for branded shopping, medical or even just some timeoff from their country. They're turnout in a night at a casino can goes up to hundreds of thousands. I doubt they will so affected as to stop spending in other area if they does lose on the table. This are the ppl the casino should be (and I'm sure they're) targetting at.
Just my thoughts.
Cheers