I guess this is one version of what a micro-transaction powered Web could look like. Potentially even worse forms of click-bait becoming dominant.
The decisions "is this fraud" and "am I prepared to pay for this" end up needing to be taken by humans, because the automated systems can be endlessly probed for weaknesses and predictability.
Why couldn't the site play games with the tip button by hiding it under other links or routing repeated clicks to it?
If it requires human interaction, the simple fact that you've asked the user imposes a nuisance cost. There's a reason that app store purchase bottom tier of pricing floats around the $1 range and not the $0.01 range.
I can't speak to Android, but on iOS the reason is that Apple has decided $0.99 will be the lowest price tier [1].
If they wanted to let people have an even crazier race to the bottom, I'm sure we'd see $0.49 apps and then $0.10 apps and $0.01 apps. With password entry there was a nuisance cost, but "scan your fingerprint" is pretty close to frictionless. Tapping the download button is the most difficult part of the transaction.
[1] https://www.macstories.net/stories/a-beginners-guide-to-app-...
if Amazon implants micro payments for content on the browser somehow, where they don't control the whole stack, it is sure to be a even worse disaster.
rest assured, no micro payment today is as bad and easy to scam as this joke.