Well, definitely an RV is going to cost you more in the long run. It's literally a life-time investment in pure recreation. A motel is a one-time expense and you are done with it. Considering the cost factor only, RV's are not practical. They just aren't. Very expensive in the long run.
However, motel vs RV??? We've done both over the years and this is our preference.
If weather is permitting, no matter where we go, we take the camper and use it for even a single overnight.
If weather is freezing and snowy and our destination is freezing and snowy too, then a motel makes better sense. Once a camper is winterized, you are limited to the ways you can then use it.
So, for example, in the middle of the Winter (like we did last January), we went to a motel for 2 days, actually Eisenhause (Middlebury, Indiana), because there simply are no campgrounds open this time of year.
As far as prepping, arriving, and reaching the point where you hit the bed, I think the time factor is probably about the same.
Assuming you boondock at a Wall Mart, hitting the bed can be done as soon as you turn your engine off.
If you make reservations for a campsite, you'll want to check web sites and maps to make sure your spot is suitable for you wants and needs (trailer length and obstacles getting into the camp site.) So, actually, to settle on a campsite vs settling on a motel room, I think it takes a little more planning and thought into the campsite.
Now, you arrive. With both you have to register (equal time for both). Now you get your assigned campsite number, or the key to your motel room.
You now have to set up your camper. Unhitch (if a towable), jacks down, plug into shore power, maybe attach water, and you're ready for bed.
Motel? You have to go check the room, then drag all your luggage to the room. And if you forget something, you have to constantly go back to your vehicle to get it. Not to mention something you might have forgotten completely, like a tooth brush or your deodorant. So now you have to make a quick trip to the closest Walmart or grocery store.
With an RV, you already have everything there. Just go to bed.
I think the RV is more time efficient. If you already own an RV, it only makes sense to use it, opposed to letting it sit in the drive way and then you have to spend even more money on a motel room.
This is just my opinion from my personal experiences. Someone else may have different views. And that's perfectly OK.