It has been ZERO DAYS since some GPL'd software made me "agree" to the GPL while installing it.

The GPL is not that kind of license: You don't need to agree to it. Agreeing to it changes nothing.

This just happens because installers have a premade "license" page and the GPL license seems like a natural fit.

But there's no point: You need to notify the user the software is GPL, but that's all.

@foone

I'm pretty sure you know this already, but it's almost certainly because whatever payware installer maker they were using had that as the stock license dialog and didn't make it easy to change.

I mostly mention this to once again shout out to whoever it was that hacked the "Agree" button on their GPL license box of some long-ago installer to read "Cool!".