Bought my Equinox new almost 6.5 years ago. It had close to 100 miles on it and had been sitting on the lot for almost 5 months (jncluding through the winter months when it was snowed on, frozen, etc.) It has been fine for over 61,000 miles. Sure it has some interior rattles, but those come from actually using the car.
There is a lot of conjecture about how new cars are treated on dealer lots and how it can "destroy" them. Meanwhile, 90% of people buy a new car and immediately start driving it in stop-and-go or city traffic the next day. If a brand new car is going to have engine problems, they are going to either be present from a manufacturing/design issue or parts issue when the car is "born", or later down the road from owners neglecting routine maintenance. Moving a car around a lot or lot porters hot dogging them (while certainly not respectable business behavior) won't hurt the car.