Travel Help improves family bonding: This is the best gift you get when you travel with kids. Today we live in a very competitive and stressful environment and parents and kids are so engrossed in day to day activities, studies, work etc that we do not get quality time to spend with each other. A weekend outing or vacation with kids gives us just that. It is one of the best ways to bond with kids.
Travel Makes kids more outgoing: Yes this is one of the good reason I believe you should take your kids out. Whenever we travel with kids and need to ask direction, I ask my kids to do that. I ask them to buy water, chips etc. At restaurant we ask them to decide the menu and order. When they go to school next day, I encourage them to discuss the trip with their friends and class teacher. All these helps a lot. This definitely improves their social interaction and make them more confident and outgoing.
Travel is a Good physical activity: Of course this goes with out saying. Specifically when you are going on trekking, beach walk etc. It is obviously better than sitting at home and watching television or spending weekends only at a mall.
Helps kids Learn to manage challenges: This is an important point. I remember when I took my kids to trekking around Bangalore. (I am based out of Bangalore and it offers some good trekking options around). Trekking can be a challenge. You leave them let them manage. Encourage them. Or when I visit another city, I ask them to find out the best 5 spots to visit in 4 hours and give them internet. Believe me kids are surprisingly good at these. Just give them challenge and they will work a way to overcome it.
They Learn something new: Yes, every place has something to offer to learn for all of us. A historical site visit will make them know more about the history of the place. Take them to nice temple and explain them the story behind. You take one step to make it interesting and they will take two steps to learn more about it. Encourage them to talk about it when they interact with their friends. That will again help in improving their social skills.