Oh, what an old thread resurrected... Having slept in a number of different hotels during my vacation and travel I can very well imagine why a tired pro rider wishing to find a good night's sleep would opt for a separate camper...
My personal opinion is that it is becoming more and more difficult to find a "perfect" hotel, in which you wouldn't hear voices from another room or sounds from another bathroom, sounds from the corridor, sounds of the traffic or an A/C fan from outside, feel smell from a nearby kitchen, in which the bed would not be too hard or too soft, which would have dark curtains on the windows... It takes me ages to make sure that the hotel I am booking is least prone to any of the above and there were many hotels to which I hopefully never return because it was difficult to have a good sleep in them.
And now during a race you are put in a random hotel in which you would maybe never stay as a tourist and you are expected to properly recover and win the next day, but due to some distraction you can not sleep well, so naturally you are not happy. I hope the hotels at least during the TdF are good enough but I recall stories of the riders that even during the biggest races you can be assigned rather poor hotel.
It is interesting that finding a better place to sleep was ruled as forbidden while finding a better place to eat (i.e. bringing your own chef and even mobile kitchen) is accepted. I think it should be riders' right to refuse to sleep in the assigned hotel, if they do not find it adequate.