Don't know how widespread this is, but as a newbie it never occurred to me until someone clued me in...
Instead of hooking up an empty hose and then pushing a bolus of air through my RV system, I outfitted my hose male end with an
inexpensive brass valve. I attach to the camp faucet, fill the hose, and then close the valve before screwing it into the RV. That way, I get only an insignificant bubble of air fed, which keeps the RV plumbing happier. Plus, if I leave the rig for an extended time, I can always flip that eye-level valve closed for belt-and-suspenders plumbing safety.
At setdown time, I can shut the valve off before unscrewing to minimize sprayback, and allow me to tote the hose someplace more suitable for rewinding and draining.