So you would be fine with your local restaurant "denying service" and locking the doors only when the food safety inspectors show up?
This is more analogous to the food safety inspectors showing up, and Uber intentionally leading them to a different restaurant's kitchen - always, even when the inspector isn't there to officially inspect them.
Nothing wrong with telling a customer their shrimp plate will be done any minute now and hoping they give up and leave.
See the keyword "intent" there? If your intent with an action is to break the law, the action is illegal.
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?
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.