HOWARD THE DUCK issue 1, from early 1976.

The hottest, hardest to find book in my time collecting up to that point. Impossible to get on the stands. Knowing what I know now, speculators bought them all up so they never made it to the stands, so they could sell them to kids at conventions and by mail order for several times cover price. In the Overstreet price guide, they call this "limited distribution" or "distribution problems", but it was speculators.

I understand there were similar artificial speculator-driven shortages for the early Barry Smith CONAN issues, and for Wrightson SWAMP THING issues, among others. The distribution problems of Smith CONAN was before my time. And for me anyway, I had no trouble getting my SWAMP THING issues when they came out.

The last I recall that happening with was THOR 337, in 1983, the first issue of Simonson's classic run. I actually years later met a guy who admitted to me he went to the distributor for the 7-11 stores in his area, and bought up all the copies, and made a good amount of money on it.
As far as I know, 7-11 stores don't even carry comics anymore.