As a fellow marketer I've totally done similar stuff to send messages to whomever is digging through their utms.
More usefully though, you can learn a shocking amount about a company from their utms and event data.
More usefully though, you can learn a shocking amount about a company from their utms and event data.
If they’re a competitor, congrats, you just found a potential niche you may have overlooked. If you look at what events they send to their analytics, you can uncover what they know and don’t know about app usage or ad performance.