1. Yes. Printer hacking isn't even "sporting". [See, any upper-middle class residential neighborhood.]
2. Any company that has open printers on their Wifi (and I can show you how to spoof their network to get the printer to switch to Your WiFi for a wee bit).
3. Also fun for IoT washers/dryers, refrigerators, toasters, security cams, and baby monitors. - But that's all residential.
Bonus: Which gets me to thinking how much IoT stuff a company has these days. I don't know.