Yet Clark hasn't had a secret identity until recently with the Blur. It's easier for him to zoom back and forth using super speed than taking the truck, he doesn't even have an apartment in Metropolis for crying out loud.
Okay, "secret identity" was a poor choice of words on my part. What I meant was that, if he wants the people around him to remain unaware of his superpowers, he has to commute the slow way like everyone else. If he raced everywhere at superspeed, people would soon catch on that he was getting around impossibly quickly. Naturally there are situations where he has to move superfast, but for everyday commuting, he has to limit himself to normal human methods if he wants to pass as a normal human.
This has been addressed in Superman stories in the past. For instance, I recently reread the anthology
The Further Adventures of Superman from 1993, and in one story there's discussion of how Clark has to travel to assignments by normal passenger transit, because if he flies under his own power and doesn't pay for airline tickets, it raises questions about his expense reports, not to mention his travel time.
You'd think that Ollie would have offered him a place in his penthouse or something like that.
As much as I'd like for Clark to move to Metropolis, I don't think he'd be happy taking charity from Oliver. Although reusing the penthouse set would've helped them save money the same way that reusing the barn and the Talon apartment has done.
Even Chloe's apartment in the Talon is a little useless now since Jimmy intended Watchtower to be their home.
Well, the Talon apartment is Lois's now. Even if Chloe moved to Watchtower full-time, the apartment set would still have use for Lois.
Like Christopher said it's just an excuse for them to keep things that would justify them keeping their name.
Well, what I said was that saving costs by continuing to use standing sets is probably a larger consideration. If, somehow, it were cheaper to set the whole thing in Metropolis regardless of the title, that's absolutely what they'd do without a second's hesitation.