I agree re the interview attire, but I don't see why 'extreme' sports don't fit in with that. Most people who are any good at them enjoy the planning, the challenge, taking personal responsibility and getting off the couch.
Aren't those good skills for a pilot to have?
The stereotypical tattoed crazy adrenaline junkie type is mostly just that; a stereotype. IME, for the most part the 'crazy dude' types don't have the discipline for that type of sport anyway. The guys who are good (defined as not ending up all over the six o'clock news) tend to be quiet, methodical and often quite conservative in other ways.