Go for a buffet breakfast and evening meal and you will only want a snack mid day.Your hotel is linked by an overhead walkway to 3 to 4 other hotels so you can eat at a different venue each time, breakfast approx $12 dollars and dinner around $15.
Walgreens pharmacy sell good snacks very cheaply and fresh fruit, that is near your hotel on the same side of the street. Tropicana hotel the food is slightly cheaper than the big four and good.
The MGM has the monorail in their complex, so its handy to get around. Downtown the food is cheaper but at the buffets there is less variety.
when you get there take the free Whats On magazine -ask for one at check in and they give you the low down/ prices for everything, food, shows, tourist attractions etc.
If you know anyone going before you ask them to bring you a Whats On back.