Beware of companies offering vouchers and cash back.
I feel so stupid, but today while checking my bank account, I found a two £10 direct debits that I didn't recognise. Of course I contacted my bank immediately, but while I was talking to them, I realised that I had bought something from Argos six weeks ago and at the end of that transaction, a company (shopper discounts and rewards) said I could claim a £15 voucher off my next online purchase with Argos. I must have agreed something with them.
I contacted them and they cancelled my 'membership' with them with no quibbles and thankfully I check my account regularly and haven't lost much.
Okay, many may say, SO you DIDN'T read the small print, but it seems I'm not alone, heres an articule written in the Guardian ---- http://bit.ly/1a4ST0i
Just be aware and careful, they work with companies like Argos and B&Q. I aslo contacted Argos to say this could damage their reputation and got a lovely telephone call from them.
I feel stupid, but if anyone can learn from my mistake, all the better.