Locally, our newspaper has "guaranteed" a delivery window. All customers will receive their paper between x and x time of the day. Cyclists might be considered too slow to get all the papers out within the window.

All carriers around here are motor vehicle transported. I think part of the argument in this day and age is insurance. While the paper may not actually be liable for accidents involving bicycle riders, they are not protected from lawsuits. The insurance on a vehicle operator probably offers the business some insulation. This is particualrly true in the case where carriers are independent contractors rather than employees.

Lastly, though you didn't specify a time of day, our paper is a morning paper. This makes visibility an issue.

I'm as nostalgic for the good old days as anyone. I do however like advanced payments to the office over the internet. I like it that my carrier doesn't change when school starts. Progress doesn't always seem positive to each of us. I don't miss broken milk bottles outside my door in the winter though. You?