Yes most if not all Home Depot locations will allow you to park your RV in their parking lot overnight.
It would be a good idea to go into the Home Depot and buy something from them even though you're not required too but if you see a home depot parking lot overnight and want to pull in their parking lot and stay a night even if they're closed then you may do so.
The worst that can happen is a cop comes by and says you can't stay there but most Home Depots allow RV parking overnight so it shouldn't be a problem.