Phones charging use such little power I’d really be surprised if anyone cared. It really depends on the place. A library I would have no issue plugging in anything without asking. I can’t say I’ve ever been at the doctors and considered charging my phone though I may ask out of courtesy if I did simply because I like my doctor. Overall I’d say it wouldn’t be a big deal either way.
Phones charging use such little power I’d really be surprised if anyone cared. It really depends on the place. A library I would have no issue plugging in anything without asking. I can’t say I’ve ever been at the doctors and considered charging my phone though I may ask out of courtesy if I did simply because I like my doctor. Overall I’d say it wouldn’t be a big deal either way.