Never before have I heard of this before...
On numerous occasions you have been notified that the outstanding balance on your account is your responsibility and it is seriously past due, however, as of this date your payment has not been received. In an effort to settle this account we would like to offer you a 20% discount making your payment amount $91.20. Please help us clear up this matter by responding immediately.
No joke! Seriously, they took 20% off my bill which is a difference of about $23. Simply because I didn't pay it on time. I have to admit, I would have paid the bill now whether they took the 20% off or not (it is one I've known was due but I've been putting off going through the stack and figuring out which are 'real' and which need to be contested with insurance). But the fact that they took 20% off my total bill simply because I hadn't paid it kind of makes me rethink my previous policy of paying things on time... I'm not sure their tactic worked?