We need to know the rules if we want to bend the rules. For a newbie who doesn't know the industry, and simply shoot for free without giving it much thought, he may be unknowingly destroying the industry that he/she hopes to be in the future. But those who know exactly what they are doing, it is perfectly OK to give free shootings as it is a way of promoting / customer relationship management that will certainly rip in more profit in the long run (aka good karma) that R a D ! c 4 L mentioned.

Of course, if the photographer just wanna practice shooting on his/her friends for fun without charging them, its perfectly fine because he knows pretty well that his/her friends will definitely never pay to have his photos taken by a outsider professional photographer. But if the newbie starts to publicly announce that he is shooting for free to anyone who is interested, then the danger of ruining the industry will come.

Well, I'm certainly not a pro photographer or anywhere near it. But I am in an industry which will share similar fate if newcomers starts giving free/ charging too low. So before anyone of us wants to shoot photos for free, pls do think twice and think deeply about the consequences before doing it. ~peace~