http://www.motherjones.com/politics/2015/12/uber-lawsuit-dri...
Uber said, "drivers get this percent from the fee, Uber gets this much". Uber claimed "tip's included". Modern philosophers claimed this makes a difference because the law prohibits taking a cut of tips.
But there is no difference! Any allocation of the fee can be rephrased as being "with" or "without' a tip in such a way that the money flows are all the same. There is no "fact of the matter" as to what part of the fee is a tip! Any phrasing can be correct!
Let's say Uber took 25%. You can say that the fee breaks down as:
1) 25% to Uber, 50% driver payment, 25% driver tip
2) 25% to Uber, 75% driver payment, no tip
3) 25% driver payment, 75% tip to driver, which Uber takes a 1/3 cut off (illegal).
If the law treats observationally equivalent situations differently because of how they're labeled, that law is meaningless, and basically just taxing you on angel pinheads. (I call the property of passing this test "nominal invariance".)
(The exception of course is when a customer gives a cash tip on top of the fee directly to the driver. But Uber definitely doesn't take a cut of that!