All businesses were built on sales calls so when you receive a call from a salesperson (which you probably have on your own staff) hanging up, bad language or insulting the person is disgraceful behavour. If part of your job is to accept sales calls and you don't like it then you shouldn't be in that position. Social media is a powerful tool now and a business could go under because of poor behavour. Have common decency to hear the person out. If you asked for information to be sent have the courtesy to respond if interested or not. After all they are building they're business just as much as the company they are calling is.