The only people who pop in are my immediate neighbours, only they don’t expect to actually come in. It’s usually to tell me they are expecting workmen , or are going on holiday, just a friendly informative chat on the doorstep.
However just after my husband died, people turned up without warning and expected to come in. On one occasion I was about to go out and said so, though I felt rather rude. Others stayed over an hour, or two, which was a bit much. But after those early days, nobody drops in. Nobody apart from family and one very close friend who always text a few minutes before to check if it is ok.