Totally not true for me - I use Bluetooth dial up networking to surf the web on the move all the time (eg. on the way into the office, settling arguments in the pub etc.)
A device without Bluetooth is a non starter for me. WiFi hotspots are plentiful, but they're all run by different ISPs requiring upfront accounts and you can bet when you need to connect to the net, you're going to be near a hotspot for which you don't have an account.
Until the advent of city-wide free WiFi (I'm in the UK), when I'm not at home it's actually WiFi that is irrelevant and not Bluetooth.