Some of these bloggers have up to 40 credit cards. They game the system by buying prepaid debit cards and loading it with credit cards, buying gift cards at one merchant and spending it at the other for extra points, buying things on sale/for extra points and selling them on eBay.

If you research long enough, you will see with enough effort you too could fly free.

I do it the old fashioned way - I own a business and buy everything on the miles and points cards and use the online shopping portals. I haven't flown economy or even paid for a ticket or a hotel room in 5 years. This actually seems like the easiest way if you ask me.