discounting

I discovered a phenomenon recently that probably should have been obvious. I have some marketing programs that I wanted to track. For example, did someone come to me because of a convention, or as a referral from another organization, or are they a repeat client from a larger business...

I am curious to know your opinions on discounting to family and friends. This is something I have been thinking a bit lately since I have many friends and family wanting to try the product. Do you do it? If yes, why? If not, why? I appreciate the replies. (I'll share my thoughts on it later.)