I think it’s great to always put an incentive out there when playing small sided games or during soccer practice. This makes the situation more intense and fun–more game like.
Keep score and give a reward to the winner or punish the losing team, say, make them run, do push ups, put the cones and goals back, or things like that. Sure, there are times to have fun, like in this video, but keep the soccer practice at an intense level by implementing incentives and up the ante. It’s good to play games like winning team stays on.