I visited TU Delft a few years ago, having unfortunately lost my debit card a few days prior. It was only a single overnight stay, so I just took a few hundred Euros cash with me and hoped for the best.

It was a nightmare. Cash was wildly impractical to use. The first hurdle was the inability to buy a bus pass from the machine at the airport with cash. Hell, you couldn't even buy a coffee from a vending machine. With every restaurant I had to check beforehand to see if they would accept cash - and the vast majority didn't. I survived, but I'm glad it was only a day.

I don't care if the stats say only 3% of retailers are cashless - in Delft, at least, if all you have in your pocket is a wad of cash, you are a second class citizen and barely able to function in society. If you don't agree, I suggest you try the experiment yourself :)