I believe a worker should be able to afford what he creates. A coffee shop worker should be able to afford the coffees sold there even if he only earns £8 an hour. A food delivery driver earns £2-£3 per delivery when delivering food. He should be able to afford delivery of takeaways.
I propose pricing be conditional on income levels. Have multiple brackets of pricing.
For people earning very little, less than £12,500, the prices are adjusted to be 27% of the full price, so a coffee costs them £1. This is so that they can afford the produce and they are paying only the cost to produce.
If you earn more than £12,500, the price scales up accordingly.
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Sliding proportional charges-the idea is good.
This exists as scaling fees https://en.wikipedia.org/wiki/Sliding_scale_fees
You card is linked to your identity and your identity is linked to your tax account.
Prices can be scaled to a maximum cost.
Would be good, but people do have multiple debit cards, and may have secret pockets. What is the force to make all information about your finances summed up?
This idea is more that your debit card decides how much you pay when you go to buy your coffee.
Usually, businesses want to charge the clients as much as possible, so, the knowledge of the buyer's purchasing power, is what every business is actively seeks to know.
Also, every business tries to maximize sales, even at a lower price. So, something like this already happens naturally, when companies choose to export the surplus of their production to countries with lower income levels.