Ummmm a spammer is a person who must create many accounts to game the system. If there was no login requirement they could spam in other ways, for example voting, on YouTube: views. Scraping is a huge part of spamming. First you need to identify what you are going to do, which audience you are going to go after.

I'm not sure if you are trolling or just being overly pedantic to argue for the sake of arguing or what but it's tiring.

Spammers scrape data and sell it to other spammers who do other actions.

When you come in with an intent to disprove you're going to be looking for holes in what someone says rather than focusing on the value. That's one of the main problems with the web and the world these days.