one of the American agony aunts, Ann Landers I think, was asked what was the most controversial answer she'd ever given. She said it was her advice on whether toilet paper should be over or under.
There is no right way, only what suits you. I'm astonished that anyone should change the rolls in other people's houses, though. I hope they wash their host's dishes as well, just to show their concern for propriety.
Reminds me of the Hyacinth Bucket type lady who was staying at a hotel. Because the first sheet was folded in at the corner she proceeded to do the same every time she went to the loo. Then complained when she ran out of bog roll. Turns out that the cleaners do this as a signal that they have replenished stock in bathrooms, so were not replacing hers.
I'd never set it to the back, it is longer to roll around, up and over, it's so much easier and less chance of breaking off. I'd never change anyone else's while using their loo. Most hotels and public areas use the up and over way, it rolls so easy, you should try it minty, I pick you out as you seem to have it hanging from a door.
Ah, but if you have a cat and it scratches at your loo roll - hanging from the front it all ends up on the floor as the roll unwinds. Hanging it from the back and it just goes round and round and none lost. Try it with your fingers ha ha.
I buy loo rolls /kitchen rolls by the gross on line... there must be a word for someone with a morbid need for paper products like my OH ? paperphile ?