How do they make money then? Whats the catch?
Credit card companies like Visa, MasterCard, etc., get a cut of every purchase made with that card from the retailer. Banks that oversee lending (e.g., Chase, Santander, Bank of America, etc) and partner with Visa, etc., get a small cut of that profit (which is immense). The banks make the majority of their profit on interest, which many (if not most) people carry from month to month.
If you pay it off every month, as long as there aren't fees on the card (this one has no annual fees), then there is no catch for you. If you don't pay it off every month, then you'll pay a percentage of your balance extra. Let's say you get a 12% APR/APY, that's 1% interest on the balance you carry each month, so if you carry a balance of $100 over 1 month, then you'll have to pay $101.
Lenders like Chase make money on credit cards because a very large percentage of people carry balances, and many of those balances are high, and so for every person like you who may not carry a balance, there's someone like me who carried a ridiculously high balance for 3 months last year as I was hoarding cash for my wedding and charging virtually everything. That 3 months of interest profit they got from me will negate hundreds of months of no profit for you.