second (and other) homes are taxed as investments. It's not a Utah thing, it's the same way here in South Carolina.
The counties where people have their vacation homes have to provide services year round, not just when you happen to be there. And can you imagine how much more complex our tax code would be if everyone was taxed only on services they're using - only when you have kids in primary school, only if you have a car and drivers license, etc.?