I have shopped in Argos twice lately & both times I have got to the pay-point & been asked for my email address. This, I was told, was to send me an electronic till receipt. Am I not going to get a paper receipt, I asked? Yes, was the answer but we send you another one too. Is this so they can bombard us with rubbish emails or even sell our email addresses on? I did not give them my details!
Me too, I told them I don't have one (even though I do), got a till receipt which I file. I think the staff get some sort of reward for obtaining a lot (or a number of) email addresses.
Many stores ask you for your contact details when you make a purchase, which can often include your postal address as well as your email one. Maplin, Screwfix and Machine Mart are among those which readily come to mind. I don't mind the small number of emails (or printed catalogues) which I end up with as a result of giving them the information (and I've sometimes benefited through special offers which I wouldn't otherwise have known about).
If you do a lot of online shopping, as I do, lots of stores have your e-mails already, New Look certainly did. I use a hotmail account anyway so don't care about spam but I really don't get much.
When you buy a TV related product don't give your address tk the retailers as the TV licence department will chase you up to pay for another licence.
I purchased an in door aerial via Amazon and the next t thing I was bombarded with TV licence warning letter despite telling them that I already have a licence.