Hey I failed at school I'm doing alright, sure I spend most of my time online and working of various projects but I still get paid..
I think and from my own personal experience, when I started learning PHP well it was when I first stumbled across MCCodes, I wasn't interested in making money. I just wanted to create a game like the previous ones I've played.
Starting here back in 2007 I was a lurker and the hostile enviroment which it kinda was in most places I though I'd better learn something before I join in, which I didn't bother doing anyway well not until I came back to playing with MCC in 2008.
So today, MWG isn't hostile nor is it full of flames (well not too often anyway) I think they want to learn web programming languages for the enjoyment of building websites as right now there is so many PHP developers and so little work, so I really don't think starting to learn just so you can earn money is a good idea nor one that's going to work well right now.
So all in all, I and most people here perhaps CrimGame, Pudda, Equinox the ones you see on a daily basis helping others wanted to learn because we wanted to, and to find out that it's enjoyable yet can be a pain in the ass was something we came across in later years.
And if you get into the more serious programming languages it does teach some values that can be used in any line of work also which is a plus.