I know it's abused like this as you say. The point is that for merchants for whom there's a lot of buyer remorse (dating sites etc) they enact clear steps to show you knew what you were doing and will then dispute those chargebacks (they have to or else they will get dropped)
Merchants very very rarely win chargebacks. They can represent all they want with proper documentation, and they may even win the first chargeback, but that win can easily be reversed by the credit card company, if the customer is persistent enough, with no explanation to the merchant. I know this because I've worked in credit card processing.
So any time you run into an issue with a merchant, if they look like they are acting in bad faith, you should just chargeback and stop wasting your time.
Having been in the merchant system for a long while, there's really nothing the merchant can do to prove you knew what you were doing and agreed to the charges. As a consumer I can like it, as a merchant it really pisses me off sometimes
