From what age have you given your DC free rein of the fridge and food cupboards?
And if they are allowed to help themselves, does it come with any caveats, especially now when everyone's home all the time and visits to shops are less frequent?
Mine can help themselves to the fruit bowl but nothing from the fridge or cupboards, but only because they're still quite young (6 and 9). I don't think it's occurred to them that they could sort themselves out from those places yet.