Mah Jong is a Chinese eatery just like a food court-type place. You go up to the counter and order your food and then wait for your no. to be called out. The food is not too bad but a little on the pricey side. We ordered the Beef Brisket Noodle Soup which was pretty good. We also ordered the Dan Dan Noodle - it was only OK.
You can ask for cups and get your own water from the pop machines. Sure saves some $ that way. Better still, order a cheap drink from the casino and then bring the drink to your table.