For a bit of (hopefully) practical advice...might be worth taking note of when he does this - for example, is he cooking and trying to get dinner out to everyone, or feeding the dog(s) while doing something else?
It's often a case of priorities, and it won't matter so much if the food's out for half an hour while you're eating, so I'll do that later...and then something else comes up. I find I'm often like this outside of the kitchen (I'm a bit germ-phobic), so I have to set mental alarms to sort it out before doing anything else.
Perhaps, in the interests of focus, it's worth you just asking if he'll help you clear up the kitchen for 10 minutes after eating? That way, you can "gently suggest" things bit-by-bit while he's doing them, with a correction every couple of days. He'll get it eventually, because it'll form a habit.
Some people just have blindspots for this sort of thing. My wife's similar these days, but has a total blindspot for safety - she's ridiculously accident-prone with zero survival instinct, so I'm always going around behind her and unplugging stuff, rearranging stuff piled on cabinets, removing trip hazards etc. Gradually, bit-by-bit, she's getting the idea...but it goes against all her instincts to do it.
(yes, I know how "accident-prone" sounds on a site like this, but...this is the woman who, an hour after I left for a couple of days for a show, managed to break her foot standing still on the stairs. To this day, I still can't quite picture how she did it...)