Natcoa was a truck camper club and a 501c (or 503b, i'm not sure which) organization. It organized caravans and rallies. Rallies often included folks from Torklift along with other manufacturers and their display products.
A rally would include a covered area, usually a building, in which sumptive feasts created from potluck dinners.
Rallies are social and educational in nature - with opportunity to see other rigs, their modifications, talk with their owners and exchange ideas.
Needless to say, a great deal of humor arose from the meetings.
It takes a lot of work and volunteers - truck camper owners doing the brunt of the work. A now aging population is probably responsible for the diminished number of volunteers - plus the advent of online social groups.
Natcoa 2.0 is now on Facebook.