Some of they make money blogging, some of they make big money. There are some methods to monetize the web content. But, if you hope you will earn a lot of money you are mistaken already.
To make money, a blogger must be able to sell and he needs to rich at somebody who wants to buy and has some money to spend.
It’s like in the real life!
I can say that I make some money with that blog, but it’s not enough to buy things I need day by day. Steel I can cover what I spend with that blog.
I can hope that, someday, the income will be greater then spendings and I will be able to be focused in creating useful content.
Some blogger, but only a few, can make a living trough the income brought by their blogs.