When my nephew is with me I do sometimes change his diaper in a public restroom.
During our summer vacation I changed him in the middle of the bathroom floor at Walmart a few times.
A few people who walked in gave some weird looks but most people just avoided staring and was trying to avoid eye contact.
Most people probably though he just had an incontinence issue and needed diapers.
I asked him if I could do it and he said yes so I didn't force it on him and if he would've said no I would've not changed him in public.
Also I've changed his diaper a few times outside on the ground at the park with people around.
He seems to enjoy getting changed in front of people and he even ran around the park wearing just a diaper, shirt and shoes.
People around that area in Arkansas are really nice and so it's pretty easy to get away with things like that and some lady just assumed that he had an incontinence issue and hated clothes.
She said she had a son that hated wearing clothes and was incontinent as well and he would run around outside in just his diaper.