Yes there are gov. regulations.
I once asked Rabbi Yisroel Belsky about this and he stated that the food “industry” has become increasingly more “defensive” about it’s labeling on account of some law suits.
End Result is that many things that are made in factories that aso produce dairy items are labeled “dairy” so the company can protect itself.
This has ramifications to the Kashrus labeling as well since they can’t reay label something as pareve if the actual label says “dairy”.