E-mail for receipt now abused for Spam.

I bought something at a Lovisa shop last week. When I wanted to pay, I was told that they no longer print the receipts, you have to give your e-mail address. I explained to the sales assistant that I do not want to give my e-mail address as I do not want any spam or mails from their company. I was also told that should there be any issues with the purchase, that I would not be able to return it without the receipt...so in effect, I did not have a choice really about giving my e-mail address. I was assured by the sales assistant that my e-mail address would only be used for the receipt and not for any other marketing e-mails or Spam from Lovisa. I stupidly believed her... I now get spam from Lovisa. I know I can just block them, and I did, but this was blatantly lying to me and abusing a system to get my details. I will NOT shop at Lovisa again while they have this policy in place.