I personally hate these especially when you have told them you are not interested but they wont take a hint. I am in marketing but I wouldn’t dream of using this method. Not only because of the annoyance it generates with the general public but there are plenty of more effective methods out there.
Before the internet became popular sale calls were considered popular by businesses however, to my knowledge they have always been seen as a nuisance by the majority of the general public.
I would seriously urge businesses to evaluate their marketing practices and see if there is another way in which they are able to gain the information that they need without cold call and the irritating sales calls.