Actually, the checkless debit-card application pilot is rather lame. It actually doesn't help what-so-ever. Here's how it works:
All cash lanes get a yellow fake check. When someone wants to apply for a Target debit card and they don't have a check on them, the cashier can use this fake check instead. However, the application never gets approved "in-store" anyways (always "requires further processing"), so the Guest never gets the 5% that day. Instead, they have to call a number on a an additional insert you have to give them, so they can tell Target their account and routing number. Target will then "approve" their account, but they still have to wait for the card to be mailed to them in order for them to get the 5% off.
Most of the people who get told about the pilot basically end up asking cashiers who would possibly want to do it, and just bring a check with them the next time they come in.