'Also, in this instance, it wasn't a woman randomly handing over her booking to a bunch of homeless people. She went though a charity who referred some rough sleepers to the hotel. Screening had happened. It was blatant discrimination.
I note, I took over a friend's Premier Inn booking in August. I turned up, said "room in name of X" and was given the key card. No ID check at all. I've passed on bookings of mine to friends with no issues either. The ID check really isn't something they are normally that fussed about.'
She was in no way entitled to hand over her booking to anyone. That's made explicit in their T&C for very good reasons, namely to do with their liability as a business as enshrined in law and for their insurance to be valid. When you book you pay for the hire of the space, it is not your property to dispose of as you wish, same as with any hire - a seat on a plane, a car, even a rented flat or house. All amendments and changes have to be permitted or you are violating the T&C of the hire and that is not discrimination, it is business.
When you took over your friend's booking without their knowledge or permission, you may well have violated the T&C of the booking and had they found out or chosen to, could have asked you to leave as a result and been perfectly within their rights because again, a booking is for the hire of the space and it is not the guest's property to dispose of how they wish.