I can't wait for e-paper to get cheaper for consumers, but I'm not looking forward to the inevitable increase in advertising displays this will accommodate when it does.
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.
Will lack of backlighting cause difficulties tho?
Counterpoint - a large e-ink advert market means (likely) cheaper e-ink products for consumers. E-ink isn't likely to replace cheap paper, it's more likely to replace LCDs and OLED screens which are already more obvious/intrusive as they're self-emitting.
In theory, the big screens could be roughly comparable to LCD screen prices, like the 6" e-ink screens already are.
They key cause of cost in e-ink is lack of demand, and more specifically lack of demand compared to LCDs. LCDs are produced at a rate of billions per quarter, they're so stupidly cheap it's almost unfair to compare them with e-ink. Point is, LCDs will always be cheaper unless demand changes.