i'm one of those photographers that dont look a day older than 18 (turned 18 two weeks ago actually), and sometimes I wonder what people think of me when they see me. It's a wonder how far the proper outfit and a DSLR can go. When I shoot my events, I try to look as formal/proper as possible (usually dress shirt/pants, vest or blazer), and carry two cameras on me (one tele, 80-200/2.8, one wide/normal, 10-20mm or 35mm, mind you i shoot on a crop sensor 'cause i'm poor)... and people seem to think i'm actually a professional, based on my gear and dress. A little gear can go far.
The problem is the misconception that every kid with a DSLR knows how to use it. I often see kids (and some adults too, most of the time they're old asian dads, it seems like every asian dad thinks he's a photographer) getting paid to shoot events that don't seem to know what they're doing. The photos I see from them tend to suck. I don't think I'm amazing or anything, but I'm not horrible, and most of the times I'd like to think I'm better than the paid shooter. These kids get hired because their Canon Rebel and kit lens are better than the host's point and shoot, not because they're good.
The sad truth is that everyone wants to be, and everyone is a photographer nowadays. Even punk 18 year olds like me :] It's easy to be a photographer when all you have to do is look like one!