It's not a big deal if Marie wears Spanx. I wouldn't want to be a celebrity and be flabby. Heck, I don't want to be flabby just because I feel better knowing knowing things are smooth.
When "diet foods"/healthy foods don't taste good, you need to remember that you are probably addicted to all the bad foods, like sugar, and you have to go through a period of detox. Eventually, your tastes will change. It is far better to eat the prepackaged foods than be overweight.