Sample gut flora of people with "auto-brewery syndrome", culture the samples, and sell them in pill form to DUI lawyers for their clients.

This is a shitty idea because anyone driving under the influence deserves to be tried and punished for their actions. But if this could be done, you'd have no trouble selling each pill for $1000.

Or, sell the pills for way less to those that want to get drunk off bread or pasta. Either way it's a totally plausible, feasible, potentially lucrative shitty idea.