Local and school sports events can foster socialization, cohesion, and investment (as in improvement) in communities. You can make the same argument for the church. Learn to work within a team is good for kids. I feel like sports taught me to cut people slack, coordinate with others, and generally just made it easier to get along with people different then me. All of these things are compatible with socialism. I'll agree that war is wasteful (excluding socialist revolutionary action), religion is complex, but sports have clear positive benefits.