Everybody is entitled to like what they like and not like what they don't like. However you make some comparisons that I don't think are accurate. CG doesn't need to advertise on TV, they advertise on their website and YouTube...which is a lot more effective for their target demographic than advertising on TV (and a lot cheaper, too). It's hardly by "word of mouth" more like "word of YouTube"...they have a viral marketing campaign which targets their demographic.
You also compare them to Meguiar's (sort of). CG is a tiny company in comparison to Meguiar's (even when you include CG's corporate parent/donor Warner Chemical Mfg. Co.), and that's even before Meguiar's was bought by 3M.
As was brought up earlier in this thread (or another thread), most auto product sales (heck, most product sales) is about marketing, image, perception, hype, mystique, etc., rather than the actual product. CG is very good at what they do in this regard.