I have always done mine myself. The back of a wall mart lot works now. I have done them in rest stops. Not recommended. I always take the used oil to a recycle place.
I'm going to change oil here at my friend's place. Her son has a grease gun I can use and I have my fluids. He'll take the used oil for chainsaw bar oil.
We try to land at a friendly place. I'm sure we'll find another friend in the next 4-5000 miles
WalMart provides free parking, but I'm not gonna push their policies by doing oil changes there. I'd hate for them to take away that privilege.