I am using my laptop and it sometimes connects on to other peoples Internet that live around my area. I have made some purchases using my debit card details and i was worried that whoever owns that Internet service will be able to see what I have bought and my card details. Is this true?
Regardless of the encryption on these wireless networks, which I assume isn't there since you can connect. Your details are still encrypted before being sent out. Noone will have been able to see your card details. Someone smart might have been able to see what site you were browsing.
I used to get scroungers like you trying to hack into my network at home - but have made sure that my password is set to 128bit which helps a bit - why can't you be a good neighbour and suggest that they set their passwords up ?