Tsim Sha Tsui Post Office

The best part about this place is that it’s not deathly busy at lunch… that’s probably because it’s rather difficult to find. Somewhere behind the infamous Chunking Mansions, next to a construction site, and on the wrong side of the Peninsula, you’ll find this place. The best approach is probably out of the East TST Rail station (L1) if you don’t mind climbing 4 flights of stairs.
As a certified idiot and newbie to the HK Post I find the layout a little confusing. There’s a «Pay Thru» lane, and a lane for «Stamps/​Registered Mail», then the Speedpost line and another kiosk for buying stamps as collectors items. Even though there’s a number board nobody was taking numbers, and there was nobody to offer any help.
I was mailing a small manilla envelope to the United States by regular air surface mail. I’d stapled the envelope shut and placed a piece of tape over the staples, lest they fall apart and scratch anyone’s hands. Here’s the transcript of the entire transaction, word for word:
Postal Clerk: You cannot staple shut the envelope. You glue or you tape. The staple cannot go through our machine. (Proceeds to yank off staples with a letter opener, in the process opening my envelope.)
Me: Oh, ok. Sorry.
Postal Clerk: OK. That’s OK. You want to mail USA? Regular? No register? No? OK. Three dollars seventy. That’s seventy CENTS. Three dollar seventy.
Me: (Hands over money).
Postal Clerk: OK! You give me four dollars, four dollars. I give you back thirty cents. (Hands me back the change.) OK. Thirty cents. You’re finished now!
I can only conclude that I must’ve looked like a complete moron about the HK post for the clerk to provide a running commentary of our transaction.
I’m also unclear whether the clerk was speaking English slowly for my benefit, or because he couldn’t speak it well.
I’m thinking the former.