Everyone here is an adult.
I'm a retired district court judge, former prosecuting attorney, defense attorney, and Assistant US Attorney. I've practiced law for four decades. I've never seen (or heard) of ONE person being prosecuted for using ANY hotel discount code. That doesn't mean somewhere, some person was unlucky. It does mean, that its likely to have never happened, given the volume of real crimes being committed every hour in the USA.
Bottom line, we are all free to choose. Frankly, what others do is no business of the the sanctimonious preachers among us.
Happy and safe travels to all.