Frankly, this is why the iPod Touch wifi, and related wifi applications, are of limited value to me. If I'm at home, I'll use my laptop or desktop to surf, check stock prices, mail, etc. When I travel, it's impossible to find free wifi. Even with those that charge, you can't figure out which are widely available so that you don't end up having to pay for 2 or 3 different services so you've got coverage in various airports, hotels, etc.
I assume that at some point soon, there will be the some consolidation of this, or wifi devices will include cellular broadband cards so you can use AT&T, Verizon, etc., wireless networks.
At the end of the day, they could remove the wifi capability of the iPod Touch and it wouldn't be a big deal for me.