When did dropping by an office become Rude?

When did it become Rude or Inconvenient or down right Prohibited to arrive at an office without an appointment? I just wanted to hand someone in the office paperwork. Maybe ask one question if they had a moment to spare.
Current situation: I'm applying for my California Massage Therapy Certification and live less than a 10min walk from the office of the CaMTC. Since I was already out getting fingerprinted and having $13 passport sized photos taken... then why not just drop in the office on the way back home and be done with %90 of the process. Easy.
Well, first there's the problem of building's not keeping their signage clear and updated. Then there was getting the security guard in the lobby to understand what organization I was asking for. Then he had to call upstairs to ask if someone could see me because they don't just take walk-ins. But someone will be down in a few minutes to see me! Great!
I look through my papers again to make sure they're all in order. The phone rings at the security desk, he answers responds, hangs up. "You can leave the paperwork with me. Someone will be down before the end of the day to pick it up." Okay, well, it's 3:45pm... Sure. I stuff it all in the envelope I thought to bring along and seal it, making sure to clearly state the CaMTC and Re: Jack McDowell Application on the front.
And as I hand it over to him I think to myself... this is ridiculous. I live 10mins walking from here but in some twisted way over years of "dealing with the public" office minions have decided that it's easier and safer and more effective for them if they never have to deal with a human being face to face. The website suggests I pay $2.50+ to USPS or FedEx or UPS (none of whom I fully trust anymore, even when you pay for insurance or verification cause there's always a loophole and never any accountability) to deliver something that is going less than a mile from my home.
All of that alone is just ridiculous... not to mention the fact that I apparently have to make a phone call to tell people that I don't like to talk on the phone and would prefer a face to face meeting to ask one simple (at least I think) question about my certification.
Who does this serve? Shipping companies, security companies, the boogey man.