Not sure I really understand where you're coming from. If this was a high spec car parked on double reds, does that give a motoring enthusiast any more reason to know why the driver parked it there than a regular driver? This is what you asked of cyclists.
I never leave my bikes locked up anywhere. Its either in secure parking at work, or inside at home. I've already had one bike stolen from one of these places.. Yet, I'm a cyclist.. perhaps even in the "cyclist brigade". I commute on my bike and go out for rides in the weekend for fun. Go figure.
Thanks also to IWAF for a less confrontational, reasonable response.