Earlier quoted context omitted.
It's likely coinbase was chosen simply because it's the easiest way for their victims to buy coins. There is a vulnerability with Pizza businesses in that they trust the caller is making a legit order, and don't ask for pre-payment before delivery thus leaving them open to fraud. Whoever is doing this is clearly bluffing and hoping just a handful of businesses pay the extortion and likely flooded the mail system with…
Yeah you guys are probably right, after all. If it demanded cash and suggested visiting your local Citibank Branch or Citibank In Network ATM that clearly would also be an equally random and meaningless data point, totally not trying to make Citibank look bad or anything.
If "cash" was a random form of currency that the pizza parlor had statistically never heard of and had literally no idea on how to acquire, then providing an address for a specific ATM would be pretty random and meaningless, yes. Would you expect an extortion letter to say "If you don't pay me one bitcoin, I'm gonna screw with your business. I'd tell you where you can find a bitcoin, but I don't want this extortionary attempt to slander the name of legitimate businesses who are trying to increase the adoption rate and accessibility of this exciting new crypto-currency"?