Okay, here's how you wear a sombrero at the movie without them getting in anybody's way: Many craft stores sell doll-sized hats of various kinds -- sombreros included -- for doll-making projects and other crafts. Just get a package of them, glue or stitch on a safety pin, and voila! You have a sombrero pin to proudly wear as a badge to the theatre. If a whole group of people do this, you will have the non-sombrero badge wearers wondering what's going on, which is always fun!
Or, you could take the small sombreros and attach an elastic to them... wear them as hair ornaments, or even small hats if the elastic is long enough. Though that might get in the way.