By that desire, the Hotel has the right to block all Cellphone services, after all they put phones in your room (and charge you ridiculous amounts of money to make calls on them).
That's actually happened. Back in the 90s, before cell phones were widespread, you typically made calls using a phone card. The hotel I was staying at (in San Diego) would block these calls, trying to force guests to pay their insane long-distance fees instead. They released the block the first time I complained, but when it happened again the next day I packed my bags and changed hotels. A hassle for sure, but the new hotel was cheaper and nicer (right on Pacific Beach), and didn't block my calls.