Anyone heard of IBIS hotel( by the airport) renting out rooms on hourly basis ?

Since the flight arrives at 6 AM, and nothing would be open at that early in the morning, might as well get fresh. That's is the thought

Arrival and being on the streets of Paris are two different things. You could be in a cab heading for Paris by 7, to your hotel by 8 or so, where theywill hold your luggage. Rather than checking into a hotel, undoing baggage, etc. So by 9 you are still at CDG whereas you could be walking around Notre Dame. Think about it.