You'd have to be insane...

...to use an open access point.

By using one you're giving the owner of the WAP free view of all your network traffic: including unencrypted passwords you might use to log in to your banking etc web sites.

Second the operator of the WAP can re-direct you to any sites he wants, even ones that appear to be what you wanted but aren't.

And you're not safe if you use a paid for WAP either: you've might just have given your payment details to a crook.