Ist For Women and other extremely Annoying telemarketers

I am appalled, firstly at the fact that these companies obtain our phone numbers and call us any time night or day to try and sell a service. But for the telecaller to be rude at the same time is infuriating. I was called by a number 031 *** and the caller told me he was calling on behalf of 1st for Women. I very politely thanked him for calling but that was already fully insured and genuinely did not have time to talk. He then blasphemed - I told him he was rude and I ended the call. How is this allowed - it is such a blatant invasion of privacy.