The half-day trip is an option obviously for someone with limited time. Often times folks are traveling through town or they are on a road trip where they have many stops and sights to see throughout the day. This gives you a chace to spend a few hours fishing and still plenty of time left in the day. Half-day trips are offered for any time of day, so you can do a morning or afternoon trip depending on your schedule. There has been multiple times were I have taken groups fishing in the morning then whitewater rafting in the afternoon to cool off.
Half-day trips have all the same amenities as the full-day trips including top of the line fishing gear, tackle, bait, snacks, drinks, comfortable seats with arm rests, and a heater for those cool days. The half-day is a great trip for kids, it gives them enough time to get some good fishing in but not to long to were they start to lose interest.