I've never gotten the whole "never been in the rain" thing. I see/hear people make this statement, especially when they are trying to sell a car, but does that really make a difference to a buyer? I know it wouldn't if I were the buyer.
Most of these cars were transported by rail/OTR car carriers, so the likely hood of them having already seen rain before anyone took delivery is pretty high. Take into account hat they also likely sat in an outside staging area in Canada awaiting transport, they probably saw rain/snow at that time, as well.
These are mass produced cars and other than the few differences in ordered options and colors, they are all the same. I think the whole "never driven in the rain" thing is just a method some people employ to make them feel like their car is better/different than the hundreds of cars identical to it purchased by someone else.