No, this isn’t a feature about saving you money, or educating you in quantum physics or trolls; it’s about the loose relationship we have with change… you know, loose change.
I’ve worked at a cash register a lot in my life, having people telling me to “keep the change” on large chunks of money all the time. 50 cents here, 20 cents there, sometimes whole dollars. I mean, how many times have you done this when you’re in a hurry?
Now imagine all the times where a cashier asked if you wanted to round up your total to the nearest dollar to support a cause?
While I haven’t taken formal data on this, and I try my best to account for cognitive bias (but nevertheless succumb to it, like everyone), from observation, I’ve seen that the majority of people do it, and I’ve heard co-workers having the same success.
Duke University professor, and renowed psychologist and economist Dan Airley
http://www.slate.com/articles/business/cashless_society/2012/03/cashless_society_what_happens_to_charity_when_no_one_carries_loose_change_.html