This type of analysis is why it is important to be clear the Bill of Rights does not apply to individuals or companies, it only applies to the government. A hotel (which you are free to use or not) that monitors your room fridge is not the same as a government that spys on its citizens without probable cause that a crime has been committed. Search warrants were invented because of past abuses of police powers and the desire to prevent it. I sincerely hope the Supreme Court gets this ruling right and rejects the Feds claim to warrantless spying.
I did a data warehouse for one of the big hotel chains and what you bought from the mini bar was part of the data they wanted. They wanted to make sure that the mini bar was stocked with what their best customers wanted when they booked a room. Some call it an invasion of privacy and some call it customer service.