As part of the final step in their education, all optometrists are conscripted into a confederation of thieves and smugglers. In fact, the "eye test" that they have you read isn't even really there to test your vision. It's a distraction that allows them the time to go through your things in an effort to steal their most coveted prize: unopened candy bars.
All of this is because the Guild of the Treacherous Eye has had a longstanding feud with a similar organization among dentists. The League of the Tooth has no interest in keeping your teeth healthy. In fact, it's quite the opposite. Not only does the ruination of your teeth give them a steady income, but it's also an essential part of a very intricate plan to seize control of the world's population.
And the sad, hidden truth is that a clan of thieving eye doctors are the only thing standing in the dentists' way.