Collecting intelligence is one thing. But deliberately abusing your competitor's systems in a way they did not intend to allow in order to collect intelligence is not only ethically wrong, but also likely illegal, as this article mentions.
Hell originated after Uber created fake rider accounts on Lyft and used software to trick Lyft’s system into thinking those riders were in certain locations. This allowed Uber to see the eight closest available Lyft drivers to each fake rider.
Creating fake accounts for this purpose is a violation of the current terms of service [1] (these might have been different in 2016):
9. Restricted Activities
h. forge headers or otherwise manipulate identifiers in order to disguise the origin of any information transmitted through the Lyft Platform;
l. use any robot, spider, site search/retrieval application, or other manual or automatic device or process to retrieve, index, scrape, “data mine”, or in any way reproduce or circumvent the navigational structure or presentation of the Lyft Platform or its contents;
When an end user breaks the terms of service of whatever system, most people would say that terms of service mean nothing. But since it's Uber, uuuuh, the scary terms of service!!!
That you have access to information (whether accidental or through deception) doesn't mean you're free to use that information any way you please. Especially when it comes to anti-competitive business practices.