I think its rude to say anything about anyones food "positive" or "negative". If I get the ole "You must cook breakfast everyday" or the looks like "yea yea.. all that salad for a 350lb woman...she will be stopping by for candy later" I swear I could just punch someone.

Quite frankly,

Its none of your business what someone buys, so it really shouldnt be that hard to not comment on it.

You dont know who what foods are for. Would you feel better knowing that their 150lb son at home wanted ice cream and they are following their low fat diet and have lost 50lbs on it already. Sorry they aren't at your magic weight - you know the one where its not so hard to stop wanting to yell and scream at them.