The advantages are that you are in a barriered Aire with no cars, and pretty sure the service point will function (WiFi excepted). You can now even book a spot online and theoretically leave and return during your paid for period and be sure of a spot.
The disadvantages are that you have to pay approx €10 per night. Some village aires that were free or you bought a ticket for approx €5 ( or like many did not pay) have been franchised to campingcarpark. Less problems for the Mayor but less income for the village.
On the whole I am happy with them, but only use them if they are in a location that suits me, such as Nantes or Saumur. Generally you can still get plenty of free or cheaper stops as they represent a tiny proportion of the total available in France.
This company are also now muscling in on the market.
https://www.aireparkreservation.com/aires-camping-car
Since they manufacture and install service points, pay barriers etc it makes sense that they copy the campingcarpark model.
We have used an Aire attached to a community sports complex in St Pierre Quiberon for years. Often it was full, but when you looked to see the tickets in the vans they were few and usually bought by the Brits. It amused me to see a French van arrive, park up and see the man walk over to the service and pay point, studiously read the information and then saunter back to their van and ignore the request for payment. It is now served by aireservices and barriered at a cost of €10 per night. Last September we were the only van staying. Many vans arrived, looked at the barriers and moved on. I have read a theory that the French believe that it is their right to park for free and refuse (were possible ) to pay.
Davy