promote it right and you won't get just whiny cxers but mtbers, 'urban' riders and everything in-between. basically do the parcour race in actually a good location with fun obstacles and you'll be on to a winner.
'whiny cxers'? Really? I don't know if you've touched a raw nerve or something, but of all the cycle disciplines I've competed in (road racing, time trialling, track, mtb, cross) I'd say that cxers are the least whiny by some margin.
promote it right and you won't get just whiny cxers but mtbers, 'urban' riders and everything in-between. basically do the parcour race in actually a good location with fun obstacles and you'll be on to a winner.