As stated, every tyre manufacturer in the world advise new tyres to the rear.
Also:
1. It's more instinctive for a driver to lift off when under steering to bring it back into line, this is what the vast majority of the public would do when a car gets out of shape. Most (new) drivers would not know to steer in the opposite direction to counter an oversteer situation.
2. With the front crash safety and crumple zones, you have a better chance of sustaining less injuries going head on (understeer) than you have swiping sideways (oversteer) - safety.
All production cars have understeer inherently dialled into them. Even rear wheel drive production road cars.