I grew up in a small town in Central Illinois and about the only time we didn't wear jeans were when we were playing sports for our school team. When we were playing pickup games or whatever we were usually always in jeans, and I played baseball in jeans until about the 7th grade.
When I was in 6th grade they put together an "all-star" baseball team to go play a couple of tournaments, and we played in jeans and plain red shirts, we didn't even have numbers, and those mesh-type hats with just a red panel in front. We ended up finishing third in one tournament and I believe second in the other. All of the other teams had uniforms and made fun of us during the games for our lack of style, so needless to say we got a lot of joy out of beating them.