you should point out that parkour is not very much of a sport, it is a discipline.....a very amazing discipline that in some ways alows you to use a loophole to get around gravity.
also,
Maybe if you do a dive roll race, or sonic roll race, they might be more interested in parkour, and wont harass you for doing it
Note: you're not really suposed to show off for parkour at all, you're just supposed to do it for yourself,
but i think that if people think what i'm doing is stupid then i have to show off a tiny bit so they have a positive attitude toward parkour, and accept what i'm doing
it's like
'this kid is soo stupid'
or
'Thats AMAZING!!'