Not knowing who is or isn't strapped, it'd be foolish to wind up dead over a parking spot. Ya gotta figure if a guy starts going apeshit over a parking spot, they're an unstable dude and unstable dudes are more likely to shoot you or kick in your window after you leave. Even some chicks are crazy enough to key your ride if you grab their spot.
As a general rule, I only steal parking spots from soccer moms with kids in the car. If shorty gets out to challenge me, I call 911 and report kids left unattended in a vehicle. But that's just how we in da RU 18th Street rollz.