Everyone loves free, other than the people who have to pay for it. This is the unsaid truth that hides behind any “free” marketing method or campaign. There is normally, though not always, a real cost in terms of time and money.
So when you find yourself tempted to offer something for free, be sure and count the cost in each and every way you need to, in order to make sure your free content, bonus gift or other promotional label you chose to give is affordable.