I took out the babies' carseats - including the bases - for the first time literally ever. We've vacuumed around them many times, but they're latched in so tight I knew it'd be a pain to get them totally out and in. Not worth it just to get those last few unreachable crumbs out.
But today I have a little more respect for those clean-nazi parents who forbid children eating in their cars. While I'll never adopt such a rule (because enforcing it would have consequences much more unpleasant than frequent deep cleaning), I wouldn't mind NOT having discovered a huge pile of crumbs large enough to feed a flock of pigeons. It was pretty gross. This picture was just one captain seat- the other was actually a little worse.
To think, all this time I've been awkwardly handing snacks back to the kids while trying to drive safe, I've thought they were actually eating. But no, they were squirreling bits away.