I don't know if it's centralisation so much as personification. Patreon wants to be a a friendly brand, part of people's self-image. And having chosen this, perhaps they can't afford to live and let live.
It's very difficult to imagine Bell Telephone (in their 100% monopoly days I mean) feeling responsible for what people discuss on their wires, or feeling a need to deny (say) pornographers service so that its other customers wouldn't feel tainted. Or Visa likewise today -- it's understood that other people will use the same plastic to pay for things you morally disapprove of, just as they could use cash. But it's positioned as a neutral carrier, and nobody cares (I think).
It's very difficult to imagine Bell Telephone (in their 100% monopoly days I mean) feeling responsible for what people discuss on their wires, or feeling a need to deny (say) pornographers service so that its other customers wouldn't feel tainted. Or Visa likewise today -- it's understood that other people will use the same plastic to pay for things you morally disapprove of, just as they could use cash. But it's positioned as a neutral carrier, and nobody cares (I think).