Might be a few grasses out there, shopping folk who are breaking the rules. I personally have several friends who are Police officers following me on Strava... but if I was to get a fine off a Strava ride - after the fact, I would probably point the finger at all my other followers before them, not only that, people in the same groups as you.
Though if someone officially complains to the police and provides them a name and a strava ride link... can they do anything, is that enough proof to issue a fine ? Strava has glitches occasionally, Garmins have date and time issues occasionally.
I'm sure if they wanted to nail a serious crime down using the analysed data off the GPS, Garmin connect, Strava and whatever else, they could do something with it.