Double dipping the Halloween candy huh?? Guess it'll be two nights of fireworks now....
Fireworks is actually where this notion really affects things. If July 4th (or 24th *) falls on a Sunday many of the fireworks displays are on Saturday. This actually works out nicely as few people have the 5th (25th) off work and going out to see the displays can result in a late night. They are also the holidays where you're largely dependent on the city, etc. for the main event so what gubmint says can really affect your plans. However, you're right, there are some organizations lighting fuses on Saturday and others on Sunday.
Halloween is on Halloween everywhere I've lived in Utah - *feces*hole side of SLC and now in a very military neighborhood near Hill AFB. There's always talk of having it another day and it never really materializes. Provo... another matter entirely I'm sure.
New Year's is ALWAYS on New Year's - LDS firesides and Provo city celebrations aside (note: Provo should always be considered apart from the rest of the state. It makes the Vatican City look like Miami Beach). I'm surprised at St. George but I pretty much guarantee the unofficial celebration will be on Sunday while maybe 40 people hit the official celebration on Saturday. St. George is a college town and it'll be mad with drunk, underage students when the ball drops.
* Pioneer Day - When Breed 'Em Young and crew arrived in the valley. State holiday with chuck wagon breakfasts and fireworks. Pretty cool bene for living here actually.
