I've always wondered this too....

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Okay, now that I posted about it and was feeling guilty, I finally cleaned it out

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~Happiness is a large family~

funny I have often wondered it myself
and I get so grossed out I clean it often

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Kelly mom to 3 great girls A Peanut, a monkey and a little burrito.

I know! I'm thinking crumbs and dust from the countertops as well. Maybe those with little hands are using little sticky hands in there.

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It's not what you make; it's what you spend.

I Take a damp paper towel and Wipe it out Every time the silverware is Getting low , and I See it.
I Wash the Trays once every couple months, I Also take the trays out to Clean the actual drawer. , and Believe me there is Lots of dirt in that drawer, Not Just in the Trays