http://www.quora.com/Aaron-Greenspan/Of-Round-Pegs-and-Squar...
http://www.quora.com/Aaron-Greenspan/Of-Round-Pegs-and-Squar...
Sure, after buying an iphone for around $200 + $100/month in data plan. Not cost effective for a "small" business owner.
"Or my friend can directly pay me back money he owes me with a card. That wasn't possible before. "
Yes, you could do that with paypal, without carrying a huge hardware in your pocket and paying less in transaction fee.
This is not to say they won't make money. They will, but many others will make even more money.
Your argument is based on a false premise. Nobody said things would change "overnight" at every level. Square is starting with the simplest case. No doubt they're hard at work building out a more sophisticated register platform that will move them upmarket.