Ask HN: Why are all the code bloggers/presenters/bootcampers online so “cool”?

Obviously, this aesthetic appeals to a certain (majority?) set of people, but when I look at bootcamp websites, Udacity, presentations on Javascript, Swift, etc. (just about anything associated with "learn to code"), the people are always causally dressed and "cool" - often a sort of shabby stylish look. Is this really how it is? I don't work in software. Most offices I've been in are full of Khaki Dockers and slightly dated button down shirts. People in these images/videos also appear to be perpetually about 25 years old. I've often considered a career change, but am turned off by what's presented as the norm, mainly for fear of not fitting in. Are you all wearing headphones and hoodies in an open office with a fancy coffee machine right now?