Thank you for the opportunity to help you with your question!
These are not
monopolies. Price discrimination is usually easily practiced in these areas
since the kind of customers who visit these areas have a high price
inelasticity such that their demand for such things will not reduce
significantly due to an increase in the price level. In addition, most of these
services are luxurious and their price elasticity to price is very low. These
issues makes it easier for these players to easily practice price discrimination.
Please let me know if you need any clarification. I'm always happy to answer your questions.