USPS wants more curbside and/or clustered mail drops. This will cut down on the amout of mail that gets read.

"Mail recipients say they read and respond to 16 percent of the mail delivered to their doors, 8 percent of the curbside information and 4 percent of what arrives in cluster boxes."

It would be interesting to examine the percent response of mail delivered to single family homes, or otherwise to the door, versus curbside and other non to-the-door drops.

http://tinyurl.com/n3lxh59