Unfortunately nowadays it is a lot easier to obtain people's telephone numbers. One day I was at home and received 6 cold callers trying to get me to commit to one thing or another. Unless people have 'unknown' numbers blocked, you cannot stop them. This comes at a price with the providers i.e. BT. The days when if your number was ex-directory meant it was ex-directory are long gone! They haunt me even at weekends and it shouldn't be allowed. I agree, vulnerable people will be taken in by their sales pitch. Something should be done.