Exceptions to Enter event in forms

I notice that a lot of modern UI components, specifically chip input fields allow a user to hit enter which adds a new chip. Google’s material framework also has an enter event for adding new chips. https://material.angular.io/components/chips/overview

The question is, is this bad UX? Typically the enter button is used to submit a form, provided the other fields are filled in that is. If this is an exception to the rule, what rules does it raise an exception to?