When someone mentions 22LR, the first thing that comes to mind is marksmanship and target guns. Small bore competitions, bullseye pistol, etc.
When someone mentions 45ACP, I think of self defense, a 1911 at the ready on the night stand, on the waistband, or in a glovebox.
When someone mentions .40S&W, I think of Law Enforcement.
When someone mentions .38 Special, I think of Law Enforcement, old school. S&W M&P.
When someone mentions .357 Magnum, I daydream of Colt Pythons.
When someone mentions 9mm, I think of gangbangers holding Glocks sideways.
Seriously, I felt self conscious buying 9mm ammo when I first got my CZ75.
There was an older guy there buying a couple boxes of 45ACP and I thought "I need to get a 1911. That's a respectable round".