It really depends on the local retailers when comics disappeared from newsstands.

Around my area, local 7-11s dropped comics in '95 or '96. I remember buying the first few issues of Heroes Reborn Avengers from a local CVS in '97. A mom and pop drug store had comics through the 90s.

And yes, the early 90s speculator boom led every idiot with a dollar to spend to believe that they would send their children to college with copies of Superman #75, Spawn #1, and Spider-Man #1. The speculator bust a few years later, when the great unwashed masses went off to speculate on Beanie Babies, is what left the comics industry damn near dead, and left comics fandom filled with great unwashed masses... but that's just the stereotypical description of the average comic fan... and there ain't too many left.