[silvestrov]

I guess that changing the paper displays cost a lot more than people imagine when you include all the backend jobs for distribution.

Being able to change the sign quickly/often for new advertisers might also bring in more money. E.g. you can now sell different advertisements on Friday versus other weekdays, and more specialized Christmas advertisement.

[ISL]

With eInk, an advertiser can also change the ads based upon who is walking/driving down the street.