People tend to eat somewhat less if they have access to high calorie foods in big, opaque packages. The story is that they learn to exercise some portion control when presented with a large volume of goodies.
Today’s invention is therefore a vending machine for snack food eg crisps or nuts, designed to help people limit their intake.
This has pictures of the glorious calorie-dense snacks, but when you select and pay for a portion, a larger amount of say nuts drops into a tray.
Still invisible, you can insert your hand into a glove (like a clean-room cabinet) and scoop what you want, by touch, into a bag.
The idea is that getting in touch with the product, in the same way as when you use a big packet, allows development of some portion control.
You select less than the amount the machine allows as a portion, because you have the experience of grabbing it and scraping it into eg a paper cup.
The surplus is replaced in the storage hopper for that particular snackfood.