Shopping with kids

Everytime I tell the boys we have to go to Wal-Mart Rion asks if I have to get a lot of things. The last couple of trips have been good because I've had short lists. Even so, we still spend an hour there. The kids want to see the fish, then the toys, then the video games and now the Halloween decorations. They spend more time shopping then I do. As soon I we are done looking at their things, it's off to get the groceries. Then they whine the entire time that they want to go home, they're done shopping. I've tried to explain to them that we would already be on our way home had we not stopped to look at all the things they wanted to look at to no avail. It's like a reoccurring nightmare that I can't wake up from.