You're in zoomed out view and you want to select a Starbase quickly, so you click on the bottom quadrant of the planet. That selects the strikecraft in the planet, clicking a second time selects the starbase. Small thing but it would make more sense to select the starbase first up. Since you will probably want to select the starbase to upgrade it, but would not want to select the hangar defence craft.
Why do Starbases not affect culture in the same way as Cap ships? If having some meaty ships circling a planet destroys enemy culture, surely a massive starbase should affect it? Possibly a SB upgrade?