To each his own. There are always anecdotes....but that is all they are. That doesn't mean every new ski is problematic. You certainly could have checked the bases with a true bar yourself...it's not rocket science!
My guess is you simply had a hanging burr. I have not had a shop tune my skis for 2 decades. I let them grind them flat...but that is it. In fact what prompted me to learn to tune besides my kids racing at a high level, was shitty shop tunes...mostly it turns out the shop morons never knock the hanging burr off of the ski. As I said, the skis only need to be flat 10MM in from each edge o ski fine, but if you have a hanging burr...your screwed. It pretty makes the skis, unskiable. Railed means they are concave from edge to edge. Generally that is not the case. Most times they may be base low in the center of the ski in the tip and tail. But that really has no effect. A hanging burr will make your life miserable. The ski won't roll on edge smoothly and once on edge they won't want to roll back off. And the harder the snow or icy or weirder the conditions or man-made....the worse it is!