Containers on tribal area's

Yesterday, I was visiting a friendly tribe in the area. They seemed to be unable to take items out of a basket. I asked them to put the basket on public just to try if I could take things out of it. I could not open the container even do its set on public. Then we tried adding me to the friendslist. That did not work either. The container was placed on tribalgrounds so I thought it would the reason.

Did anyone else experiance this? It does not sound verry logic to me that you can't put any basket accesable by non-tribe people.