Yes, they existed, but I clearly remember they weren’t a common thing in 2002-2003. At least not in Latvia. Around 2005 I worked at small ISP in Riga (main reason for cheap and fast Internet here - lots of competition), then WiFi at home was already more popular. But real explosion happened with iPhones and later Androids.
Discussion
Okay. Maybe in Latvia things moved a bit slower. I am only speaking from my experience in the USA and from my experience selling these devices.
In 2004, when I started dating my wife, we drove around my town with a laptop and a WiFi PCMCIA card and detected over 200 insecure WiFi networks. I used this as a marketing campaign to secure people's home networks. I don't remember how many secure networks I found back then though.
