Why do they alwasy peek into the fridge ?

Ok, as strange as this sounds this is the 3rd time it has happened at my cribbs !!

Friends (females) walk in, chit chat and eventually they tend to find themselves peeking into my fridge and then the conversation goes something like " Oh, you do groceies and cook too ?" - yeah-- its like a question mark at the end of the statement ?? , I maybe single and live alone, does not mean that I am a junk food addict and can't cook for myself.

Ok, to all yea woman out there-- what is interest with a guy's fridge and whats in there ? No serious question  :)-

For the love of your species I still cant figure this one out.. so help me out !!