I just had a thought: Why are there no girls on Tattooine...?

There are. There's the two major ones, Beru and Shimi, but there's also several women shown in Jabba's palace. I haven't watched the prequels since I was a kid, but I assume there's probably a lot of shots of women walking around town, too.

Aunt Beru and Shimi Skywalker.

They all ran off to Vegas?

they are the sand people... 😶

there were some, just not Humanoid girls.
ir was there one of those Head tentacle dancers?

Because it was blown up. The planet doesn't exist.

I'm sure there are. It's just that we all know only men go adventuring. /s