Well, my kids are pretty young yet (5,5,3), so I don't let them have "open access" to the fridge or cupboards. They get into the fridge sometimes anyway when I'm busy doing something else, and guess what they like to eat?! MARGARINE!

. They'll bypass applesauce and even pudding to eat the darn fatty maragarine. I've also caught them eating cottage cheese with ketchup mixed in; and they've been known to eat plain sour cream too.

. So, given their ages and what they like to eat, at this point I monitor (or try to anyway!) what they are digging out of the fridge.
Also--Dh and I do like our junk food (so sue me

). We almost always have chips or ice cream around that he and I eat after the kids are in bed. Kids get junk food too, in limited moderation. But if I had an open access policy I'm sure they'd eat it all the time.
As they get older, no doubt I'll let them get their own snacks whenever they want. My parents always let me eat whatever I wanted from a very early age (I sometimes wonder if this is why I'm so fond of junk food

)--we had a lot around the house when I was growing up, and I inevitably ate it.