Spying on other teams regardless of the technology has long been regarded as unsportsmanlike conduct, across all sports. This is nothing new and if anything your attitude to win using spying is against the norms.
Edit: I'm sure they don't refrain from watching the opponents playing against other teams too...
The "unsportsmanlike" aspects isn't about the difference in intelligence gathered, but avoiding the need for every team to run counter-surveillance operations.
Sports is definitively not war, and not all is fair. Otherwise why ban doping, or disapprove of Tanya Harding getting her competitor kneecapped, etc.