I'm just curious, why so many rifles that fill the same role? A 270, 308, 7mm-08, and 30-06 are all very similar calibers and cover much of the same 'area' of purpose. I have a .22, 30-06, 338, and 458 win. My next rifle will be either a .223 or .243 to fill that gap between .22 and '06.
If the front action screw hole is only slightly too deep, I'd just grind a smidge off the end of the screw so it doesn't bottom out before tightening down on the stock. I realize it's a new rifle and you shouldn't have to fix Mossberg's flub, but it's such a small thing with an easy fix. I personally wouldn't see it as a big deal at all. The other option would be to see if the local hardware store has a couple washers that will fit on the screw before putting it into the stock/action.