So as long as you use it reasonably it should be fine. As a primary Internet connection would be unreasonable
Seriously...this is like debating with the people who think it's okay to bring Tupperware to an all-you-can-eat buffet.
It's more like management kicking you out after they've felt you've had "all-you-can-eat".
Whether it is ethical to enforce a no-tether policy is a separate debate.