I'll keep that in mind. My general self assessment is that I speak in a rather clear, easy to understand manner at a moderate volume. Usually a guest approaches as close as they can get as they are explaining what they need. Typically I defensively step back as they approach, which may be encouraging them to get closer for whatever their reasons may be. I'll speak louder to see if it helps though.Maybe you should look at yourself to see why so many step so close. Are you soft spoken? Are you taking into account that if they are stepping close then maybe you should raise the volume? I have the opposite problem, so damn many people mumble or speak so soft that I would need to read lips to tell what they want. When I say "I can't hear you, you're very soft" they don't raise the volume. I step forward in hopes that closing the distance will enable me to hear and they step back and keep mumbling/whispering. Indoor voice isn't library or movie theater voice, so really look at how loud you normally talk and try talking as loud as if you were standing next to a diesel engine and needed to be heard over it.
Unfortunately yeah, a lot of it comes from foreigners however, there is a good mix of locals in the mix of "Surprise! I STINK!!" Category. Women and men too.Is it mostly foreigners?
I know many overseas countries don't have a problem being real close to you when conversing.
The whole 3-feet apart rule is very much an American thing.
Not to defend them. Could just be social unawareness on their part. It is creepy when our norm is otherwise.
But yes, just step back.