Any time you read an e-mail and it gets you, out of curiosity, to go to a website, the marketing company that produces the ad copy and mass mails it gets .01-.10, whether you actually spend money or not.
In some cases, the marketing company will get a percentage of your sale if you do spend on that first contact.
Spam is all about money. Even if you don't spend money the site with the most traffic (hits) can sell more ad space for links to other sites where you might spend money.
That's why it's called the world wide web. It is a wonderful source of information and the greatest way to communicate world wide.
As with any information source you have to realize that people tend to be biased by their own opinions and take it all with a grain of salt,as they say. There's a good question. Who are They?