Here, most of the restaurants and many of the motels let ANYBODY charge for free, even noncustomers. But they may have different rules for noncustomers where they only have one charge station.
Here is an example. Look at all the photos there. You will see me charging my Experia there as I was having lunch on the opposite side of the river.
Where they have more charge stations,
such as here, the policy is do not bother to ask, just plug in anytime, even if you never plan to be a paying customer there.
Many places are pro-EV and wish to help out all EVs. Perhaps the owners are EV owners themselves, I do not know.
But I do know it can help them also. For an example, before the city of Yerington, NV had any public charge stations at all, during a trip, I went to the Chevy dealer and asked if I could use theirs while I walked to a nearby Mexican restaurant for lunch. They were extra friendly and very nice, and I did not even own a Chevy or plan to buy one at that time. A few weeks past and I decided I wanted an EV car at each of my houses. Without even checking the local dealers in Reno, I went to Yerington, NV (115 km from my Reno house) and purchased my new Red Chevy Bolt.
Click on the photo here and see my smaller Energica charging in May of 2021. That free charge is what made a +40K$ car sale for them.
-Don- Auburn, CA