I recall sitting outside hall A in 1993 or so, of the then SDCC (I believe it was limited to just hall a and b, maybe c too, don't 100% recall), and unscrewing fortresses I had bought from my buddy chris (pedrin, invented them) and putting my "big" purchases into them...
of course, back then, the lot across the street was a dust bowl, and there was no close hotel, so I lugged them around or stuck them under a table in the comic heaven booth...
I suspect if it worked then, it would still work today, even if not very practical (plus, I haven't seen chris set up at a show in many a moon)