It really depends upon whether I’m eating alone or with others.
I just love foods with lots of sauce, juice or gravy and if there’s plenty to go around I’ll take extra sauce. Naturally, I’ll use some bread to mop up the remainder if I’m at a restaurant or eating in others’ homes. I see nothing wrong with that. Sometimes the sauce is the most delicious part.
To me, it seems utterly pointless to always leave something on the plate for the sake of propriety. If there’s something I don’t really care for, of course it gets left on the plate. But if it’s really delicious, why on earth would I want to leave some on the plate just to look good? It will just go into the garbage. What a waste.
So, to answer the question, I’ll mop up anything that’s delicious because it would be silly not to. But if not enjoyable it gets left.
If I’m eating by myself, I many times use a largish bowl rather than a dinner plate. And since there’s no one to be offended by it, of course I’ll lick up every last bit of delicious sauce. Why not? I’m all alone and it’s delicious and efficient as well; makes dishwashing a whole lot simpler. Since I’m alone and I enjoy it, I see absolutely no reason not too. It harms absolutely no one.
And, as Hearkat mentioned, when I’m at a restaurant, I linger and savor a delicious meal. Im constantly having to guard against an overzealous server trying to clear my plate before I’ve finished so I can certainly relate to that.
If it’s more than I can comfortably eat, I never hesitate to take the rest home even if it’s a pretty ssmall amount. I paid for it so why not? Obviously I don’t lick plates in a restaurant but that’s what bread is there for. I never eat bread when they first bring it prior to the meal. That makes little sense to me.
As a kid, I was raised to be a member of the clean plate club but I tossed that nonsense out the window when I reached adulthood. If I’ve had enough, I stop eating. I don’t keep stuffing my face no matter how delicious. That’s what doggie bags are for
As long as someone is mindful of good manners and restraint when eating with others I don’t think it should matter one bit what they do in the privacy of their own home.