I suppose it depends on whether you believe if I left my door unlocked and someone burgled my house, whose fault it was.
I'd say a bit of both. Yes, people shouldn't be leaving their wifi unsecured, but at the same time I see no reason for them collecting this data except for nefarious reasons.
If it wasn't an accident, why hadn't they deleted it
three years later, despite ICO demanding them to do so?
http://www.gizmodo.co.uk/2013/06/ico-go ... s-or-else/