Advertising totally subverts and corrupts the invisible hand. If that doesn't make sense, draw a diagram of the forces that move the invisible hand in a straight up consumer-producer relationship for your website. Now add in advertising into the picture. Note that consumers spend just as much if not more than before, only the cost of the website appears free, but is baked into an entirely unrelated product they pay for.

That cost may be substantial. There are many products whose marketing cost exceeds the cost of making and delivering the product or service. Movies, many prescription drugs, long distance phone service, soft drinks, vitamins, and many online services are mostly promotional cost. There's an argument for taxing advertising to push this down.

The real issue is that these people and groups and projects need to be protected in the same way as journalists for the mainstream media used to be.