Well, I started in the early Eighties, and if I got GAS, it was because as I got better at shooting, I realized I needed certain items to help improve my photography. First, I realized I needed something other than just a 50mm lens. Then I realized that given what I shoot I also needed fast lenses. Then I got into motor drives, so I wouldn't have to take my eye away from the camera and risk losing a good shot.
And I got into Leicas when I realized shooting acoustic shows in small clubs with a SLR was not a good idea (especially with a motor drive), and I needed something which would let me shoot without incurring the wrath of the audience or the performers. Started out with beat-up second-hand M3s, but once you start shooting Leicas, you want a new one of your own. This led to me getting an M6, and it's gone on from there....