"I just played a game today and we were winning till the moment 3 of them got oracles. "
That could also be said like "My build was ruining the game of their whole team, until they bought oracles." Even though it is unfortunate for all the Teemos and Shacos out there, but I think it is very fair to have a way to detect those poisonous mushrooms and scary boxes. I have smelled more than enough of mushrooms even with oracles in the team, and gotten scared to death by those boxes. I have even walked on them when I am the one with Oracle; you don't always have the time to clean them out before moving forward after all. A detection method/counterplay is a necessary part of Howling Abyss; currently that is Oracle.
That reporting you do for oracle use sounds very Teemo-mushroom-like to me. I would not do that. :(
I don't play Teemo myself, but I love Jhin. For some reason I don't worry about Oracles when I play him though. I guess it is mostly because his lotus traps are much easier to disarm than Teemo's mushrooms - they don't even require Oracles. They are very different compared to the mushrooms and boxes. Jhin traps are not a good case for your anti-oracle selling speech.
Oh, and the rare case when I play Shaco, I go for AD Bruiser build. On him I use the boxes for peeling (They do CC, but practically no damage), so I guess that is why I haven't seen enemy using Oracles on my Shaco matches. I sometimes buy Oracle against AP Shacos though. I pretty much always buy it against Teemo. Those things are too poisonous to feel safe to walk without that Oracle eye. I repeat: Counterplay against them is necessary.