It would be difficult to return the car and not get charged for new tires. Even with regular rotations and light driving, the tires wear quickly and the dealer will be looking for a way to measure tread depth in such a way that they need to be replaced. There is a reason many off lease cars sitting on a lot are on a shiny set of brand new tires.
Also the tires are horrible in the snow as has been noted. For some people they are "OK", but overall they don't incite confidence in winter conditions like stopping and turning.