A.C.
Most towns have a farmers market nearby. Go browse together! Often there is live music. You don't have to buy anything, but if you have a few bucks there are always good treats. The Cache Valley Gardener's Market is every Saturday morning and is one of the best I have been to.
You could also go mini golfing, bowling, hiking.
Logan canyon has First Dam which is a beautiful picnic spot. Also the Wind Caves are nearby, a great hike and you can picnic at the top and see the entire canyon. Breathtaking!
A lot of parks in Utah do free concerts. Pioneer Park has a free concert series, also some coffee shops have live music. The Gateway in SLC is a great place to do outdoor shopping, listen to live music, play in the fountains.