In Paris hotels have been extremely tightly regulated for a long time. The original system of 1-5 stars originated there, and was a government-mandated scale based on very specific criteria of quality and facilities. Lots of sharp practice by hotel-owners is outlawed. For example, hoteliers are not allowed to 'bundle' meals with overnight stays. This stops them selling meals of worse quality or higher price than cafes and restaurants. Given the regulation, it seems fair for them to expect that the authorities will crack down on unregulated competitors.

You might argue the pros and cons of the regulation, but it's clear that over the last 100 years, Paris is known as a great place to visit, and the availability of decent and decently priced accommodation has been very successful for the city as a whole, not just its landlords.