I think it has been around forever. Most people I know hate it, but there are still companies that put pressure on their agencys to "follow up".
That beeing said, its probably a low-effort thing that still has a medium to high chance to bring in customers.
Update: If you work in a company and force your media guys to do these cold calls, please stop. Nothing gets you faster on blacklists.
Yes, it is frustrating if no one picks up your release, but then you have to adapt and choose either a different topic or a different target audience. Me, for example, I never write about personal changes in companies. And still people ask me if and when I publish my piece about their new Head of XYZ.
You can also send abuse reports with the help of SpamCop[1].
And of course, if you use GMail/Google Inbox, marking them as spam also helps.
[1]: http://spamcop.net/
But I think I remember seeing emails in spam with an explanation text that said 'this went to spam cause you marked similar messages as spam'.
Also, it seems to be learning when I move emails to Promotions/Forums/Updates/etc., so I don't see why this wouldn't be the case for Spam. Maybe it's only for my account though.
Now i look forward to cold emails.
Two weeks later:
"Just checking in to see if you'd seen my email!"
... or something along those lines. Best part is when there is an "opt-out" link.
Just do the responsible thing, and contact the abuse department of the sender company, and the "mass mailing" service they use. There is spam coming from their systems, they should be made aware of it.
As long as email continues to be the primary communication medium of the internet, companies will spam people through it. It takes exactly zero effort to set up Mailchimp and run a 50K email campaign. Everyone reads email. If the subject is curious enough, people will read it.