To expect the kids to understand that when I say "What is xyz doing on the floor?"...

[Ihavenoideaatall]

That I mean for them to pick it up and put it away/in the bin/whatever!?

Kids age 7 to 12 so not little ones. I have asked them if they understand what I'm getting at and they say they do.

But they still don't listen...

What are the consequences of them not doing as you ask or are there none? Do you discipline them in some way or just shrug and do it yourself?

As a teenager I'd never have tried this but I have been known to answer "what is xyz doing on the floor?" from housemates/XH etc since with. "Very little. Seeing as it's an inanimate object." But then I have turned from a fairly untidy child into a very untidy adult.

I will always make them do it even though it takes more time and energy than doing it myself.