Sure, my fellow noob! I was in a similar situation with bartending and soda.
(Bring a meal to work, for starters, if your boss will allow it. Starving through an 8 hour shift is terrible and unfortunately, really common --> It'll make those bars look like a steak dinner.)
I started bringing hoity-toity soda to work with me, which kept me away from the fountain soda (it always felt like a treat, and I enjoyed the hell out of it), and slowly started subbing spinach-blender drinks, teas and the like that I brought from home. So maybe in your case, pick up one of those fancy-schmancy dark chocolate bars from a different store and wrap up 3 squares in tinfoil to take to work at your store? Then, when you feel like inhaling a mars bar, suck a square instead.
Just a suggestion. No idea if it'd help. But good luck.
