As a young person, I signed up for my first credit card less than two years ago. Now I have six.

Almost all of them I signed up for their bonuses (usually small, as I wanted to start out with no annual fee cards with good cashback, and I had little credit history at first). Two of them had fees. The first, a hilton card, allowed my partner and I to spend many nights of our cross country move to the west coast to be in comfortable hotels in the center of their respective cities, including free breakfasts, as well as allowed me to use airport lounges on a few flights for the first time.

I am a grad student who makes $2600 a month...there is no way I would ever be able to afford staying in some of those places, nor could I ever justify paying for an airport lounge. Needless to say, i got incredible value out of a card that cost me 100 bucks for the first year that I have since downgraded to the no annual fee version.

Another card was the American Airlines Aviator Card with Barclays. To get a sign-up bonus of 60,000 points (worth little more than a domestic round-trip for two people) and a companion pass, I used my card once and paid the annual fee of a hundred bucks.

I know the credit card companies are hoping that I don't pay off my balance, or that I keep the card and pay the fee, or that I will be afraid that my credit score will drop (which it hasn't), or any number of things could go wrong such that they can make a buck off of me. But it turns out, in the age of the internet, information symmetry means that it is pretty easy to play the game in such a right way such that you benefit the most. I don't take risks (like manufactured spending), and I wait several months between getting a new card. And so far it has worked well for me.