There might be legal reasons with vat or age restrictions why anonymous payments would not be viable. GNU Taler is not about microtransactions, though they obviously strife to cover that nieche.
The idea with a wallet system for lack of a better name, is, that instead of many small payments, you make one bigger payment and have the smaller payments be made more easy. Cause at the end of the day, you want to have money transferred onto real banking accounts. And those want money for their service. International money transfer and currency exchange are additional problems.
A defacto implementation is seen locally with many services. Like Steam, if you pay them up front. Then you do not have to transfer money each time for a cheap game. Also seen in many platforms that use "Points" or whatever they call their in-platform currency.
Ideally there would be a service that implements this crossplattform. Paypal could have been such a service, but they suck big time. Foremost because they do not behave neutral, as a payment service should. They impose their own arbitrary restrictions. But in a more practical way, they just relay the money transfer to the real credit card companies. Each itty bitty payment over paypal is a complete transaction on my credit card bill. Waste of transaction cost that could have gone to the developer.
Makes me wonder why there is not such a thing already. People want this. Probably the big fish have not interest, because they tink they can sell more by taking and converting money into points that are easier to spend, because they are not called money.