Why are specific media dominated by particular specific scams?

So it seems that each scam (or very dodgy) industry has chosen its delivery media. There is a separate thread about car warranty spam calls, that media seems to be dominated by just that industry, but you don’t see them on other channels so much (for me its at least 80% of spam calls seem to be “your car warranty has expired!”, with IRS/collections scams making up most of the remainder). For Facebook hacks it seems to counterfeit sunglasses are the dominant industry, whenever I see an obvious hacked post tagging everyone in someones friend list, it is usually related to Raybans (does anyone ever buy, or pay for, a pair of sunglasses this way?). For spam email (back in the day can’t remember getting one recently) it was famously boner pills.

Why is that?

It’s all about creating a sense of false urgency. Even I fell for one like that once. “Do it now or be fined/ charged!”
Can’t figure out the sunglasses one though.

About the boner pills, I remember reading about a decade or so ago an article in which the author went through with the offer, ordered some pills, and actually got them.