It's more like the restaurant suspecting someone of investigating them and giving them a different class of service. The analogy is totally busted though, because these investigators didn't show up at Uber and ask for info, they just went around using the service.

Nothing wrong with telling a customer their shrimp plate will be done any minute now and hoping they give up and leave.

Yes there is if you believe that customer to be a health inspector and you move set up your shop somewhere else with the intent of evading said health inspector.

See the keyword "intent" there? If your intent with an action is to break the law, the action is illegal.

Of course the intent is to avoid them. Why should that by itself be illegal? If they want to review your business they can do an official inspection. Interfering with an investigation, as long as you don't have an order not to do so (i.e. to preserve evidence or something) should be your freedom.

Now the part that Uber is hiding up someone elses wrongdoing makes a bit more sense, but still seems to be the same kind of thing. If investigators wanted to know, they should have gotten an order against Uber and audited their records.

After all, I encrypt communications. Sometimes with the explicit intent of making sure LE can't see what I've written. Should encryption be interfering? All the people suggesting we wipe devices before crossing a border, is that not the same?

When you encrypt the message, you are not exactly stringing people along wasting their time. When they say that they'll send a car to the inspector, they are tying up regulators' resources in order to sneak away. That's interfering with their work.

Now, the reality is that these inspectors don't need an explicit order to inspect you. If they did, then Uber should simply take these inspectors to court or claim that any evidence they found is inadmissible. Tying up their resources and getting away is beyond simply hiding something, it's purposefully diverting their resources somewhere else. If they simply didn't respond to regulators asking for a car, maybe you would have a point, but they're tying up these resources.