I sometimes believe that the police here (or rather, those that control them) find it easier to make examples of (mostly good) folk that fall foul of unjust, or at the least, less important laws.
Less hassle than going after the real, hardened, violent criminals. Makes them look good too, when they have high arrest rates.
To be honest though, I think most of our police men and women are good guys that are just bound up in so much red tape, paperwork, and are still expected to hit quotas.