This summer (2016) I have spent 2 seperate weeks camping in diapers. Both times were tent camping, with vehicle accessible, once nearby and once via a one mile hike.
Both times there were many people at camp (in one case about 20 family members, in another case 27 youth scouts and leaders).
I wear 24/7 for incontinence, so I didn't have much choice, but I was discreet.
Distance to vehicle did not really matter, as disposal was done in trash cans: in one case closeby, in the other case a 1 mile hike.
I wore diapers 24/7, except for swimming. (I don't care if I wet while swimming in a river or lake).
I always changed my diaper in my tent.
I usually laid on my sleeping pad to change.
I wore on average 3 diapers during the day/evening (Tranquility ATN), and one at bedtime (Confidry 24/7).
I usually put them in a paper bag for disposal, about 3 at a time.
No one ever noticed.
Backpacking in disposable diapers would not be attempted. I would take 2-3 cloth pocket diapers and cloth stuffers for that situation, and it would be very difficult to be discreet.