Actually, the musical is set in River City, probably Davenport, our rival across the Mississippi, portrayed in small-town stereotypic fashion as tiny, close-knit, backwards, and absurdly prudish.
So we loved it.
Besides, there's a lot of gay subtexts going on.
Into River City comes con-artist Harold Hill, played by Robert Preston, who is most famous today for the gay-positive Victor/Victoria (1982). He intends to con the townsfolk by pretending to start a boys' band, and then absconding with the money he's collected for the band instruments and uniforms.
Everything goes fine, until Hill's former partner, Marcellus, who is now "legit," shows up. They have an unspecified previous history; perhaps they were romantic partners. At any rate, Marcellus doesn't express any heterosexual interest, except for the novelty song "Shipoopi."
Oh, he also cured her little brother Winthrop of his speech impediment, surely with some gay symbolism along the lines of "don't be afraid to be who you are."
Big city types have been transforming bigoted, depressing small towns for a generation of movies -- and even curing speech impediments. There's a reflection in To Wong Foo (1995), with three drag queens.The top photo is of Josh Walden in something else. You're not going to see a lot of beefcake in the men decked out in early 20th century costumes, unless you drop in on a rehearsal.