It started as a joke for me. Really.
I was in grad school at the time and was (apparently) really aggravating to my supervisor. He was/is an extremely intelligent man, with tastes far more advanced than mine. He listens to Opera, reads classical literature, attends the symphony, ballet, etc. Being a lifelong (thereabouts) star wars fan I thought I'd get him an Obi-wan figure as a joke and put a Vader figure on my desk. I was pretty sure he wouldn't pick up on the analogy, but he did, which impressed the heck out of me. To this day he still have the Obi figure on display in his office, which is entirely out of character.
As mentioned in the vintage section, I never collected the old figures. I did collect Marvel comic figures, Secret Wars or whatever teh current action figure series of the time was. I only ever grabbed one or two sparingly, maybe that many in a year. So I sort of knew that the figures had just appeared in the toy aisles fairly recently. Didn't have much money in grad school, so my purchases were very limited to say the least. Essentially, I just stumbled on them. I'm not now, nor was I then as critical as many here, I was just happy to have the figures, heman or not.
Initially there were about 12 figures and Leia, who was the original shortpack in this line, monkeyface and all, was one I had no difficulty finding. I picked up those 12, thinking that was about it. When more straggled out, I would pick those up as they came along, following the packaging as a guide for what was available. Eventually it became an insanity, on the retailers part. So many figures out: POTF2, cinema scenes, SOTE, vehicles, beasts, 12". I resisted the whole time, only buying main characters and that was about it. I was not initially aware of the diversity of figures. Being in Canada, in spite of all that crap on the shelves (which I own most of now) I had no idea how much I was missing.
I eventually started doing searches on the internet and found RS in its first year on the web and eventually found collectstarwars.com as well. I was a ghost at those sites for a very long time, from around 97 onward. The whole time, until late 2001 I only collected 3 3/4 figures.
No idea about promotional stuff, but I do remember one thing. I used to see more parents buying stuff at that time, probably owing to the re-release of the OT in theaters. I remember scouring pegs with a woman that was a parent of two kids. She was asking all sorts of questions about what the main characters were and whether her kids would like things like Ugnaughts. It was a fun conversation that won't be repeated these days.
I never really followed what was coming up that closely, just occasionally printed out a new check list so I could see what was missing. At the time I was a carded only guy but eventually space issues drove that out of me too.
So essentially in my case it was dumb luck, or fate, depending on your point of view.