You hear about black hats working from coffeeshops on public WiFi, but I'm wondering how you would be able to completely mask your IP when doing this. I realize you would obviously use a VPN, but before you can do this, you need to make a connection to WiFi, where your MAC address is going to be used during this initial setup.
Because of this, wouldn't there be evidence of traffic from your IP on this network right before connecting to a VPN? Or is there some way around this that I'm not thinking about? Basically wondering how a black hat would actually hide every trace of their IP, or if this is even possible?
This answer discusses this chicken and egg problem somewhat.