I read the article, and they're claiming it's not gratuity, but it's de facto gratuity. The reason they're claiming it's not gratuity is because automatic gratuity is prohibited by Minnesota law.

Much like Obamacare "it's a fee, not a tax", but then the Supreme Court decided that it's actually a tax, so the individual mandate could be repealed like a tax. Just because they claimed it doesn't mean it's reality.