The ‘who certifies the certifiers’ question can pretty much be applied to any industry. The creator(s) of every certification program, or even college course, started it without being ‘certified’. So to answer your question, yes, these programs are based on the experience of the person (or people) that offer them.
As far as marketing, you probably aren’t going to be asked by a customer if you are certified… however, i still believe that there is a marketing benefit. Like Bill said, it’s another way to set yourself apart from the competition. If you have two equally reviewed companies… where one has certifications from training programs, and one doesn’t… i would imagine that people would generally tend to choose the one that does.
As far as education, they are generally most useful to people new to the industry. As with any program like this, it shortens the learning curve.
A lot of people are dismissive of them, but i have never really understood that stance, especially since the same people are also often complaining about uneducated workers. In my opinion, more education is a good thing. Every industry certification program had to start somewhere, and that’s where we are at now in this industry… not necessarily perfect, but improving year by year.
Regardless of your personal opinion about certification programs, here is the one thing that is less subjective. I’ve done a ton of research about these programs, and i cant recall one single person who said that they got ripped off, or didnt learn anything. Quite the opposite… i have seen many people praise the programs, and say that the confidence/knowledge they received directly led to new jobs.