Bake the noodle:3_Why don't they put any ads!

What is the meaning of not putting any ads on a popular site. Take Wikipedia or Seth's blog for an example. They don't have any ads. Why? What are they trying to prove? Are they trying to make things sound more noble by showing off that they are not making any money out of it. Let's say you are going to make a valuable site that would help people immensely. Do you have to follow this code? Would it hurt to put an ad in a corner of your site? Facebook shows many ads but they don't disturb us at all. Sometimes it helps us discover cool new things and they become very helpful. 

Isn't it dumb and inefficient to not put any ads on your greatly helpful site. Does it really defile your purpose/intentions or is it just a common misconception. If you have a website promoting charity work, wouldn't it be a lot efficient to make money from ads and donate that money. If people have really noble intentions why are they showing off that. Bake your noodle and find ways to make things more efficient. Discover what disturbs the visitors and what helps them and you.

Push your mind to its limits and decide what you are going to do. Which is going to benefit the world most: showing off nobility, hard work and commitment or the smart, efficient things done with much easy?