[linkregister]

Touch screens in Maryland give a receipt that you voted. But the votes themselves are not included on the receipt. The purpose behind this is to mitigate people paying for votes in a very close district. Having a reliable method of determining someone's vote compromises this mitigation.

Is one threat greater than the other? I actually think the threat of vote payment is lower due to the the high risk of the illegal act being exposed. But this is strictly intuition and I have no actual knowledge of the matter.

Edit: in the article, they describe a receipt method that matches your description. But the voter doesn't retain it.