Why do some shops have fitting rooms open and others don't?

[ssd]

I though no shops were allowed to have changing rooms open, although not sure where I read this?
I was in one store today and they told me the changing rooms are now open. I was just surprised?

I can't be arsed with bringing home to try on. I have done previously with large orders etc. Or if its hot and I'd rather do without being crammed in a changing room.
But sometimes if juts a hoody or whatever I'd try on top of my t shirt in store.
Cant now and cba buying and potentially returning I also don't have fund to buy multiple sizes in the first place

I was in a supermarket today and saw a top I liked. No changing room open. It's 8 miles each way. Even though there's the same one 0.5 miles away ( but needed the larger store) the staff member said buy it, try on in toilet and exchange if needed.
Otberwise it's a trek back, with kids bleugh

I was talking today to a friend who works in Fat Face. She was saying that their changing rooms are shut.
It’s silly because I will order a load of stuff online and then return what I don’t like as there is a post office at the end of my road rather than go into the shop.

Last time I went to a clothing store the changing rooms were open, and I don't recall them putting the outfit to the side afterwards. My son works in a mens shop and they steam the clothes after people try them on.

Me and Dd went to a large shopping centre about 40 miles away last weekend. No changing rooms were open. Notices up in H&M saying not to try stuff on in the middle of the shop.

I didn’t buy a single thing as I wasn’t running the risk of something not fitting and then having to do an 80mile round trip to return it. Dd bought stuff and went and tried it on in the toilets.

I would rather changing rooms were open than people tried clothes on in the public loo. Changing rooms much more hygienic. I saw a group of teenage girls trying on outfits in the shopping centre loo and discarding unwanted ones on the cubicle floor before stuffing them back in a bag to return! Yuck!!