@Laura2592
If it's a condiment, we leave it, especially if it is squeezable so virtually no chance anyone touched it or put their flatware on it.
If it is something opened like milk or juice we throw out the liquid and recycle the container, because as someone said you don't know if anyone drank out of the carton.
if it is bread we put it out for the birds in the yard.
if it is fruit, we will either leave it for the next guests or use it in cooking or might put out for the birds and squirrels depending on what it is and how ripe.
We would either leave eggs for next guests or use them ourselves.
Leftover take out we toss and recycle the containers.