You'd have to be budget conscious, but it's doable if you're not eating anywhere sit-down, don't drink soda, and don't get snacks. But yeah, the average person is probably spending $100+.

For example, at Hollywood studios, the oats at the star wars location are $7. A chicken club and fries for lunch at ABC commissary are $18. A pizza for dinner is $12. That's $37; not sure what it would come to with tax.