Interesting, most credit cards with rewards I have seen in Aus have substantially higher interest rates which is where I assume they capture the cost of rewards back. Is that not the case in the US?

As for fairness, I agree they should go away. Companies with margin can swallow the fee, companies without could be unprofitable and make no sense if they don't pass on the fee. It's a practical reality of the dollars and cents, but it is a private apparatus we opt into so I guess we can't complain that much.