I'll add the open data link to the relation for future reference. But really this kind of thing is incredibly common, and Boulder is even a pretty mild case - take a look at Commerce City's boundaries! https://www.openstreetmap.org/relation/112806

In reality it barely matters to anyone - this person is on city water and sewer, gets to their home on city streets, and has Boulder on their address - the only difference is going to be in their property tax documents. Closing this one for now, plenty of other municipal boundaries to fix if we are getting bored. ;)