Oh, an airport taxi. That explains part of it; the taxis at the airport have a terrible reputation (the only taxis drivers that I ever get into fights with are the ones from the airports). Again, a little too late (but useful if/when you come back, or for others coming to Beijing):
If you suspect you are being cheated by a driver, or have any other reasons for concern, simply start visibly writing down his taxi license number (not the license plate, but the plastic card with his photo that is displayed on the dashboard of the taxi). The moment you do this, he knows that
regardless of what he does, you have the means to report him; and furthermore, you're giving him the silent message that, "I know how things work in China".
I used this just a few weeks ago; on returning to Beijing from a business trip, an airport taxi driver started [rule 8]ing and complaining to me because my destination was "too close" to the airport, and he wouldn't get enough money from the trip. He then started telling me that I would have to pay a higher fee, to compensate him for his apparent loss.
I said nothing. I simply grabbed a pen and paper, and started writing down his taxi license number. He immediately apologized, and left me alone for the rest of the trip.
And the official receipts have a little scratch off box which sometimes entitles the owner to a small prize (like a scratch-off lotto)
This is, actually, one of the coolest and most practical ideas that the Chinese gov't has come up with. Taxation is still a relatively new concept in China, and getting businesses to issue proper receipts was extremely difficult. Then the gov't introduced these receipts that all have the lottery scratch-off section; you can win up to US$ 250 from these. Of course, most of them you win nothing, but the result is that Chinese customers absolutely demand to get receipts so that they can have a chance to win.
In the year following the introduction of these scratch-and-win receipts, tax revenues from businesses in China increased more than 400%.