What's the deal with all these 'Viral' sites.

[Inhibition]

I see a few of these being dumped every month on Flippa. It's usually listed like this:
20,000$/month profit! viral[keyword].com
And their basic strategy seems to be buying traffic on taboola/fb/outbrain/etc sending the traffic to some lame article like "10 ways to do x", plastering every page with a ton of ads from 10 different ad networks and scaling once they hit a profit.

So.
1) Why are these people selling em? Can't they just keep milking the cash cow until it stops working?
2) Why are people buying em? The sites themselves have literally no inherent value, the content sucks and all the traffic is bought, I guess they're paying for the paid traffic strategy?

I'm just a little lost on this whole trend, would love to be more informed.

 

[Potatoe]

1) Because it takes them 10 minutes to setup a new one. Wouldn't you rather cash out at 20x over and over while you wait for the cow to die?
2) Because, like the majority of website buyers, they're wantrepreneurs and they don't really know what they're buying.

 

[finnegan]

I'd like to see a walk-through of this method in the Digital Marketing Crash Course.

 

[miketpowell]

Because the profit dies off quickly at scale.

When you first start all the ad networks you slap on the site pay "average" ad rates. As time goes on their systems optimize for what the traffic is really worth and all the high pay advertisers ad you to their blacklists. Your eCPMs get cut by 90% overtime pretty much.

Kind of like ranking a website with spam tactics and selling it before it gets penalized.