Does the concept of the "gift economy" have any validity or value?

I recently read "Lynchpin," by Seth Godin, and much of the book is devoted to the "Gift Economy." One of his explicit messages is that you can make lots of money by sharing your skills and talents without charge, by making "gifts" of your time and talents to customers, who will later pay you for your time and talents. It's my experience this can be true, but I think he's conflating benevolence and good manners (and maybe marketing 101), all of which can be very helpful in advancing a career, with the giving "gifts." What role should "gift giving" play in a free society in the field of economics? Is a "loss leader" or "free sample" properly viewed as a "gift" when you know a large percentage of the people who accept it will not do business with you? Another argument Godin makes is that tremendously productive people have given "gifts" to society. This sounds a bit like Ayn Rand's concept of a "pyramid of ability." Should the super-productive, who have created tremendous value for society, think of themselves as having given "gifts" to society? "Gifts" are given without expectation of payment or returned value; am I correct that to be morally good must be non-sacrificial, in that the giver should receive some non-monetary value in return?