Did Luke never think, "What would a freighter pilot be doing with a light sabre?" Wouldn't that be like a gas station employee owning a Lamborghini?

I thought Owen gave the freighter captain story, and Obi-wan gave him the (from a certain point of view) truth.

Maybe Alec Guinness was saying "fighter" and it sounded like "freighter"? That's all I can think of. Off the top of my head I don't recall him saying either. He specifically told Luke, "He was the best star pilot in the galaxy." And he also mentioned that Luke's father was a Jedi and owned a lightsaber, he simply did not reveal the whole truth about what happened to Anakin at that time.

>>2
This. Obi-Wan very clearly states that "That's what your Uncle told you. He didn't hold with your Father's ideals. Thought he should have stayed here and not gotten involved." and "Yes, I was once a Jedi Knight the same as your Father.". So he dispelled Owen's attempts to keep Anakin's true vocation from Luke.