That’s not how it actually works, though. The merchant banks charge a per-transaction fee. Credit cards are typically 2.9% plus 30 cents. Patreon charges your credit card/paypal/whatever as soon as you click the button to subscribe/pay.
Patreon always charged those fees, but previously split it out as a “payment processing fee” which they charged the creator, and then different fees if you used Stripe or Paypal, who also charged a payout fee. Creators always made less money with a ton of small transactions versus a smaller number of larger ones, this just wasn’t exposed to their patrons.
I see your point though, you’re saying they should batch-up all of a user’s patronage to a single transaction to minimize fees. And yeah, that would be a nice innovation. And those fees should definitely be paid by the creator to avoid confusing the patrons.