I love G1, as it's now known. Back in the day it was just The Transformers, and from what I remember, it was huge. The closest thing I've seen to the level of promotion and fanfare since then was the hype over the live action movie. But back when I was 13, it seemed like you couldn't go anywhere without seeing a Transformer somewhere.
Transformers succeeded Star Wars in my and my two younger brother's affections as the toys we all loved. We always wanted the newest ones, but rarely had any money to buy them. Mostly they were given as birthday and Christmas presents, and occasionally just as random gifts from grandparents. We did manage to buy a few here and there, but never as many as we wanted. I still have memories (possibly my memory cheats, but who knows?) off seeing an entire aisle devoted to Transformers at Toys R Us, and large sections at K-Mart, or Wilsons's 5 and 10c store, or even the local Revco and Sears.
All three of us would get together in my room and have battles, trying to imitate the voices we heard on the cartoon, which we watched every afternoon after school. This resulted in the toys being worn out, with stickers coming off and chrome being rubbed away, and joints getting loose. The toys were actually treated like toys.

We used to love pulling out those old checklist posters with all the Transformers that were available and wish we could have them all. The battle scenes on the back of the boxes also did a lot to make us want the newest Transformer.
It only took a few years to grow out of them as I hit high school and my interests went in other directions. But I did remember the Transformers fondly, and I kept all my old figures boxed away. I also collected the Marvel comic until it was cancelled. I bought the occasional new figure even if I didn't play with them any more. I got Powermaster Optimus Prime just because I was excited to see a new version of Optimus Prime. I got Legends Starscream at K-Mart, and Action Master Starscream as well.
When I started buying figures again in the late 90s, I discovered Ebay, and discovered that those original Transformers I remembered so fondly were once again obtainable. It enabled me to go back and get so many figures that I had wanted at the time, as well as pick up boxes to store the old figures in, because of course when they were just toys, who cared about the packaging?
I don't know why this particular toyline has stuck with me as something I still enjoy collecting today. But it has, and it's a hobby I enjoy tremendously. And it all started with those low-articulated metal and plastic G1 Transformers that I enjoy to this day.