You clearly have no idea how most trades work, so let me clue you in.

First, most trades get the materels they need directly from a wholesaler, not from an office or depot. Why have stock on hand when your guys can just buy what they need directly?

Second, most trades don't start and finish the day at a depot or office, they drive from home directly to site. I've gone over a month without visiting the office before.

Third, a plumbing company will typically have multiple plumbers, and will try and limit the driving they do anyway, because they pay by the hour.

Finally, why are you talking about New York City? Why not use a local example?