Are you talking about interest for carrying a balance, or the various fees you get hit with if you screw up (eg. late fees, returned payment fees)?
Carrying a balance and paying card interest rate when secured and unsecured loan rates are several if not ten or more percentage points lower (card interest was 20-23% in 2019 when bank loans were under 10% in my economy) provides the profits which allow richer card holders to avoid costs. This still feels like predatory behaviour to me.
His "i got the points be like me" is herbalife marketing of the gilt edged lifestyle which attracts the chumps who pay the cost of his fee free rewards. Its not implicit, it is explicitly why they offer him and his income bracket the deal.
As one case in point, most of American Express' flagship products don't even allow you to carry a balance (and thus pay interest).
Source: work in the industry
Issuers tend to specialize, too. For instance, banks like Barclays, Chase and Amex only (intentionally) target prime customers. Chase has been known to fire customers that suddenly start carrying significant balances on their cards, for instance.
On the other hand, banks like Capital One and Credit One explicitly target subprime customers and make the vast majority of their income from interest. Whereas Amex makes 90% of their card income from annual fees/interchange, for C1 it's more like 90% interest/10% interchange. Chase is like 65/35 Interchange/interest, for comparison.
For Amex, the simplest rule is that any card named after a color (Amex Gold, Amex Green, Amex Platinum etc) doesn't charge interest.
Oh - and the Amex charge cards don't actually have no limit. They do have a line, it's just hidden (and somewhat larger than most credit limits). Amex actually has a 'check my spending power' tool on their website where you can plug in a hypothetical purchase and it'll tell you if they would (hypothetically) approve it.