I think somehow is legal, but it would also depends on the content, I saw a some and mostly offering free content for their experiences, like Youtube 360 Videos, some Free 360 pictures and some free games too.
It's a very interesting question, because in some countries you are able to play some games in some stores, some of those games are paid games, but for the store is the only way to show how the experience actually is, because nobody can describe that well something which play with the way you perceive the world around you in the VR worlds.
But in other hand, I know some (old) Arcades need to pay an extra amount just to be able to receive any profits from the game.
I think right now it should be free of charge for those who offer the opportunity to get some profit by doing that, because we all need more interest on VR now and that's a good way to get it.
BTW Welcome to the forum, for your name I can guess you speak Spanish too, Bienvenido, aquí también hablamos un montón de otros idiomas
