I'd consider the asking to be impolite (since it wastes time with a silly conversation), so I'd just take it, since, other than modest latency, it's not a scarce resource.
The asking is pure signalling. Never once did anyone actually say to me that they wanted the last piece. Like adding please, saying good bye or thank you.
I was just referencing the OP wrt conversation. However, I still consider it wasteful and impolite, since it's not merely a polite-sound attached to another message. It's a complete attention-getting, conversation-interrupting message in and of itself, with, apparently, no content.
For me it's a mix of not wanting to ask, and not wanting to ruin my appetite. These two combined forces are usually enough for me to leave it in the basket.