Remote tire pressure/heat monitors and theft

I’ve seen several of these tire pressure/heat monitors advertised here and it seems like a helluva good idea. I’m not a fear-based kind of guy, but a high speed blowout is worrisome for me. However, that said I’m wondering how often these tire monitors are stolen, at $50 each it could get pricey. Can one take them on and off without losing tire pressure? I envision putting them on before traveling and taking them off when I set up in a camp ground, though I suspect they could be stolen just as easily while in a rest area taking a rest. I also noted that internal ones are made, which would solve the theft problem. However, unless done with a tire replacement there’d be an installation expense. I don’t mean to be paranoid or cheap but I was financially devastated over the last few years and can’t afford something like this only to have some dirt-bag rip me off.
Steve