"I would add a tip" does not mean tipping is customary.

Tipping is uncustomary in China; the rare exceptions do not apply to your situation here.

USD ok.

Gate person 5.
Driver 10

Tipping UBER and LYFT "ride sharing employees" is not customary in US, but if you are aware of their avg pay its lower than the 15/hr minimum wage enacted in LA. At least give them a cash tip for gas.^

Well there weren't five weeks ago!

That's ridiculous!

OP - hopefully by now you've realized that all bar one poster has recommended not tipping. Ergo, tipping is not the norm.

That's odd. I was there more than 5 weeks ago, and I'm normally a little directionally-challenged after disembarking from long-haul flights in premium cabins. I definitely followed signs that were clear to me, and was through in seconds.

You tip nobody. And if you were to, then you have to do it in local currency. They can't pay rent or buy groceries with US$. They have to waste an hour waiting at the bank to exchange it. But then again, no tipping is required.

I had one of the building guys assemble some Ikea furniture for me a few weeks ago. While this service is technically free, he spent an hour of his time that he could have used to play cards with the other maintenance people. Had I not tipped him, I'm guessing he might not have been too willing to help next time. I was just back from HK at the time, so I gave him hk$200. He didn't seem the least bit upset.

In a rural area, tipping in foreign currency would be frowned upon.
But employees of a 5 star hotel in Beijing should have no problem
converting foreign currency.

+1 when cny hits and you realize that the foreign currency in your drawer is worth y30,000, it's not especially hard to justify cutting a lunch short by 30 minutes in order to convert.

Reading FT before travelling, I concluded that most times one of the main counters was marked, and sometimes it was actually open!

Needless to say, none of the main counters mentioned the visa free transit and our guide took us straight to the APAC/Diplomatic desk instead. This was a low level desk (rather than the higher podium type used elsewhere). We were through in 5 minutes (there were 5 of us - lots of stamping & cross checking of e-ticket receipts).

Data point - we landed at 9am on a Saturday, the main lines were empty when we got off the plane (we were in J) but by the time we got through immigration they had backed up some way.