Yes, obviously. My original point was that if, say Pete, wanted to be a trainer, it wouldn't take much. And while many jobs will have different qualifications, the certifications you can get doing an at home course are the same as the ones you would get anywhere else. Of course if a gym were hiring, and they had an application for someone who was certified as a trainer, and someone who was certified as a trainer with a degree in health/fitness/etc..., they would probably choose the second.
IMO, and I've been into fitness for about 15 years with various degrees of involvement, is that personal trainers are overrated. You're far better off in the long run doing some research and getting a dedicated buddy to go with you. I do agree that if you've never worked out before and have no interest in looking up the information yourself (books/internet/magazines), doing a couple sessions with a trainer might be for you.