But the main reason is how the location-based augmented reality game has radically changed the behaviour of its players.
Because you have to move around the real-world environment to collect Pokemon, the game and its players have become intertwined in all manner of real-world activities - from happy social meets to robbery and finding dead bodies.
And that's getting some organisations worried.
One such is the UK National Society for the Prevention of Cruelty to Children (NSPCC), which has released a parent's guide.
Called Tips and advice for keeping children safe on Pokemon Go, it notes the risks for children range from spending money to meeting people they don't know face-to-face.
But, in a strongly worded statement a spokesperson has gone further.
It's deeply troubling that the app's owners have ignored many warning signals and well documented child safety concerns.
"It's deeply troubling that the app's owners have ignored many warning signals and well documented child safety concerns," they say.
"It would have been better if they had taken time to reflect on these and put their young users first.
"Pokemon Go is setting a precedent as the first augmented reality game on the market in the UK. It's very disappointing that child safety isn't at its heart."
In the crosshairs
Of course, it's not surprising that such an organisation has raised such concerns, which are not specific to Pokemon GO, but rather to its popularity and location-based foundation.
However, it does highlight the scrutiny that the game will now receive from the media, and various organisations and governments department as its global rollout continues.
In particular the US and EU now have very strong child privacy and data laws, which some companies have been fined for breaking.