While I lament the downward spiral of the perceived monetary value of photography, and I lament the existence of people willing to give it away for free to strangers on a massive scale, I hold the principles of freedom in higher regard. If there are people willing to freely do so, there is nothing to do about it, but lament.
Blame the technology. The internet and digital. They made it so easy for everyone to capture and share beautiful and spectacular that the world is inundated with mega gazillions of it. While the motivation to share it for free ranges from vanity (“look, ma, someone liked my photo enough to use it”) to the altruistic desire to “spread the wealth” (thanks, BO), that is, to spread the beauty, it ultimately boils down to free will, the existence and defense of which I fully support.