My boyfriend and I are renting a room weekly at a local motel while we search for an apartment. My brother, who pays for the room, visits about once a day to check on us and make sure we don't need anything. The owner has yelled at us several times and told us we can't have visitors in our room. My brother doesn't stay with us, he just comes to check on us for a few minutes and then leaves. He doesn't use any of the accommodations, and doesn't do anything wrong. Can they forbid him to come to our room even though he pays for it?
A motel is private property. As such they can have whatever house rules they feel are appropriate, as long as those rules don't violate the laws of the community, state or country they reside in.
So yes, a hotel can restrict access to the rooms or any other part of the property. And it is not uncommon for such restrictions to exist, especially in bigger cities where "undesirables" might want access to indoor facilities, etc.
Your best bet is to have your brother call before hand and meet him in the lobby. That will keep the manager happy, allow your brother peace of mind checking on you and likely make your stay more hassle free.
It seems to me it is up to the motel to allow strangers in the rooms or not. It could also depend on the local laws. When you signed the rental agreement, did it mention anything about unregistered guests?
Once my father was staying at a hotel and I tried to visit him, but the hotel forbid me to go to his room! They said that only registered guests could go to the room even if I could show a document which stated that he really was my father. The policy was clear: "no unregistered guests on room for any reason"!
You did not specify your locale, but the policy of not allowing visitors has a very broad usage in Europe, most prominently in Eastern Europe.
The origins of the policy can be sourced to different motivations: liability insurance, overcrowding, hotracking, and crime (such as prostitution and drug dealing) to name several. In light of this, it's a reasonable policy, and many proprietors are often happy to turn a blind eye as long as things are low key and reasonable. Or in Eastern Europe, if the right tip to the concierge has been made.
You wrote: "The owner has yelled at us several times". This is abusive behaviour and possibly even unlawful behaviour if your safety is threatened as a result. It should be reported to the police (captured on video if possible).
Comments above suggested that the alternative is to get a refund and check in elsewhere, but the answer to your question is: yes, they can forbid him and generally with the law behind them.
These rules are put in place for insurance reasons single rooms are made for one person double rooms are made for two to three people if something happened and it was found out that there were two people living in a single room that would be a violation of building code. I had the same kind of running me my sister and her husband we're living in a motel till we could move into our new place my sister didn't tell them about me because they didn't think it was a big deal the owner found out and flipped out told them if they found me on the property again my sister and her husband would be kicked off the property. Is it right absolutely not the lady kept saying to me I know what you're up to I'm watching you. Some Motel people can be very rude so it's better to avoid conflict at all cost it's not worth losing your money because many places will not give you a refund if your kicked off their property. I don't agree with the rule at all but it's something that they put in place for insurance reasons