If you go to the park with the Razor, it will not be used. If you take the time and effort to pack it up and carry it from the car, it will assure that the Razor will be ignored for other park activites.
If, however, you leave the Razor at home, you will discover that every other child at the park has their Razor with them that day. It will be the only thing your child can think to do. They will gaze with envy and longing at the children whose mothers' brought the Razor. They will talk endlessly about their love of the Razor and misery over leaving it at home.
And next time, you will bring it, and it will bruise you in the shin as you try to walk with it from the car, and they will have no interest. Ad infinitum.