When I first attended shows in the late 80's, I was able to walk up the day of the show and buy a ticket at the box office, not to mention camping in the parking lot of the show. Once that gig was up, I started trying to get mail order tickets, and the first two tours I got denied, but was able to get them by calling in the day or two after the sale date. Once I got on the GDTS mail order list, I was able to always get tickets via GDTS, and never had to worry about waiting in line. I had the same experience when I started getting tapers tickets. First couple of tours they said No. Then, I got my first tapers tickets, and never was denied again.
I really never cared about the straglers in the parking lot (when they were not affecting things), but everything for me changed at the Meadowland shows where Adam Katz was killed. After that, it seemed the clamp down was steadily getting worse and worse. First the camping, then the security, then the merchandise cops, then checking your tickets to get to the lot, etc,etc,etc.
For me, it was about going to see the Grateful Dead, and everything else was a fun secondary event. When it was manageable, you could get tickets at the venue, but when it got larger, I played by the rules, got my tickets as early as possible and never went to a show without a ticket. I never could understand driving to a show to sit in a parking lot without ever seeing the band.
And when I got to a show, I always tried to find the most quality seat. For a show like Vegas, I could not understand sitting in the last row of the back bowl, my friends loved it, but I always had to be in front of the repeaters, and usually a lot closer than that.
I got to travel coast to coast - I have driven i-80 from New York to San Francisco seeing the dead along the way. but I always had a ticket to where I was going.
The incomprehensibleness of the size of the shows for me was the Vegas shows and the buckeye lake shows. There were so many people there it was insane.