Who is more nerdy? The nerd, or the one who follows with posts about nerdiness?
-or-
Takes one to know one! 
IMO, anything that has implied personnel should be locked. Capital ships can't be flown at all effectively by one person. In a way, implied personnel is how mobile spawn points are justified in a game-setting. So, things that big, no stealing. Anything below is fair game.
I can understand why some people would want to keep a row of tanks/starfighters in their base locked. It stops lone-wolves from speeding over and stealing stuff. Still, in those rare times when you're driving a speeder, taking damage from somebody tenacious on your six, but manage to stop and escape, say, near the enemy base... I'd rather be able to jump into the enemy's vehicle and get back to the fight, than have to run all the way back or suicide.
I'd rather twenty lone-wolf dinks stole tanks for each time a better player is able to turn the tide by getting into a nearby empty vehicle than never be able to drive one, at all.
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a.k.a.: Grandma Tarkin // hQ.Terrorek
Today's spelling/grammar tip: There = a (sometimes conceptual) place. "There is my car." or "There is such a thing as magic." // Their = posessive. "Their meat is full of worms." // They're = contraction of <they are>. "They're crazy!" // "They're trying to put their shoes up there."