I have seen both of these in use at Sigsbee in the Keys. Now, portable water is available close to the campsites (less than 1/4 mile) but the MH guys just drive over and fill up.
The TT and 5th campers stay set up and hump their water. The big one (110 gallons) I saw in use by a TT guy who filled it in the bed of his truck and drove around filling other campers since his tank was only 40 gallons. He needed a 150 dollar 12 volt DC water pump to transfer the water since the inlets on most campers were higher than the bed of his truck.
The other user had a smaller water bag he put on the roof of his truck. (NOT my first choice as I have no intention of denting my roof; but he had an old truck.) By being on the roof, he used gravity feed to fill his camper.
I use several 5 gallon water bottles from Home Depot (the bottled water kind). I took one of the caps and cut a tight fitting hole in the center and press fit a clear vinyl tube about 3 foot long into it. I drilled a small air hole in the capto improve water flow. I fill the bottles and drive them to the camper. Inverting the bottles with the hose in the fill port takes only about 3 minutes for each 5 gallon container.
I initially buy two when I get to the campground; use the water to drink; cook; and make coffee; etc. The fresh water tanks on the camper were filled at the potable water spigot when we arrived. When we need to refill the fresh tank; the blue bottles are empty and can be used to hump the water.
At the end of camping we just return the bottles for our deposit before we go.
I posted the photos of the cap and hose previously. I will try to copy and paste the url (using wife's iPad <sigh>) with an edit.
Lou and Laura with Bella - German Short Hair Pointer
2008 GMC Sierra 2500HD Crewcab SB Allison Duramax
2010 Flagstaff 8526RLWS - Superglide 3300
HAM CALLSIGN - KC3FFW