So, fun fact, I actually reported a crime last week.
A few days later I got a "Caller ID blocked" call and was like "Scammers?" but I'm the kind of person who at least answers the call to say "Fuck off" if they're scammers and it wasn't a scam it was some nice lady whose job is to sift this endless pile of crime reports.
She didn't treat me with contempt, though of course she's not going to magically make the crime not have happened, or - given I wasn't sure who did it - even commit to having somebody actually do anything about it. But hey, that's statistics for you.
I disagree that somehow picking up litter is different. You're not going to magically make there not be any litter are you? No. But nevertheless in aggregate it has an effect.