Not even a bit
Cabarton. Say it to your hosts for a bonus point. We will see who actually reads these things...
Not necessarily. You can get to every event of the weekend by uber/lyft or public transportation. That said, if you want to hike or travel beyond Salt Lake City, it would be ideal to have a car.
Kids are more than welcome at the Friday welcome party! It will be casual! As much as we love the little ones, the wedding ceremony and reception will not be a kid friendly event. Parents night out!