Strange.
I haven't got calls like that, but once one guy from Spain (I live in Finland) called me and offered me to open an account with some spanish company and buy stocks.
Well, he called to my GSM phone so that cannot be cheap for the company. Devil made me do this, but I was pissed that they thought I'm so stupid as giving money to some foreign company to buy me stocks, so I asked that guy to tell more. I didn't listen, of course, more than what I needed to say 'yes' in appr. right moments.
Then came the important moment, when he asked how much I want to put in my account. I said 1 million euros. I heard how that guy took a big breath. Then I said 'haloo, haloo' are you still there? I can't hear you...shit, this went dead...and then I shut the phone.
It was fun to watch how that desperate guy called my GSM for 4 hours. I put it in silence and didn't answer, of course...
I'm an evil asshole, buaaahahahaaa...