With plastic bottles of Pepsi nestled in my arm, I am in the check-out line at the campus store here in China. The cashier sees me take out RMB (ren min bi, the Chinese currency) and gestures to me to go to the third line. I now realize that all students are paying with electronics in the first two lines. And in the third line, I am still the only one with cash-in-hand.

Some students pay with transponder cards. Unlike our credit cards, these are read without sliding in a credit card reader, or inserting into a chip reader. We know about these cards: when you slow down to that 20 mph as you go through the K-Tag lane, the electronic reader and your windshield transponder card communicate with each other. Several attempts have been made to introduce this technology in the U.S. for payments but it just hasn’t spread widely.

Transponder cards have been used on Chinese campuses for nearly a decade. Eight years ago at Nanjing Normal University, I stayed at the old downtown campus but lectured at their new campus south of town. A faculty bus shuttled between the campuses. The card could remain inside billfolds and purses and was just waved in front of the reader as you got on the bus. Since I was there only a week, one downtown host professor would reach in with his billfold and “beep” me into the bus with his card, and when I finished teaching at the branch campus, another professor would do the same to send me back.

Back at my campus store, I count the number of seconds for the student in front of me to check out. He has four or five items that the cashier quickly scans from regular UPC barcodes, just like here. He then waves the transponder card over a flat pad. In less than 2 seconds, the cashier sees the acceptance, and nods, and he is on his way.

But more than half of the students are now taking out their cell phones while the cashier is scanning the product barcodes. The student then holds up their phone with a big square QR code. The cashier shoots an electronic hand reader at their phone, sees the acceptance and nods. That takes about four seconds. Cellphone-based QR reader systems have spread like wildfire these last two years. It is one of many apps on Chinese cell phones. And everyone in China (with the exception of some remote rural folks far from civilization) has a cell phone. Phones and service plans are far cheaper than in the U.S.

So I step up to buy my Pepsi and count the seconds after the cashier has scanned the barcodes. It is about 12 seconds before I get change back and leave. I have held up the checkout line. And if I only have big bills, it will take even more time to make change.

China did not invent money-less payment. Singapore got rid of paper money over 20 years ago using earlier electronic systems. Hong Kong has struggled to go electronic, but as a major tourist hub, they have far too many tourists who are not wired up. And China is not completely into digital money…yet. 70 million poor people remain in poverty and although many have cell phones, they do not have the bank accounts. China began using QR codes on its printed train tickets in 2010. But this major public adoption has occurred in just the last few years. Even the street vendors selling fruit outside the campus walls use QR readers.

The campus here at NW Agricultural and Forestry University is large (think Kansas State University times two)! Many ponds and gardens around campus have plants labeled with metal tags, now updated with QR codes so you can point a cell phone at the tag QR and it will provide pages of information about the tree or shrub.

The square QR code (an abbreviation for “Quick Response”) is one of three barcode formats used for airline check-in in America. The QR square holds far more information than the common UPC bar code. And sure, the U.S. has QR codes in use here and there. But its rapid adoption in China reflects the accelerating pace of modernization that is now normal here.

There is a concept called “path dependence.” Once the QWERTY typing keyboard was widely adopted, we would not re-train to use a significantly faster Dvorak keyboard design. Simply, once you proceed down a path, you will continue to go down that path without much change. While the U.S. is still swiping cards and chip-reading, China is heading down the QR path leaving paper money behind.

Meanwhile, I have less than a month left in China, too short a time to make installing a QR reader app on my cell phone worthwhile. So, I will still be that slow Westerner holding up the line buying my Pepsi with real money.