Rooftop sealant - new from factory?

Hello! I am interested in a 2017 model new Winnebago, on clearance at a dealer nearby. There were some little things that indicated some water damage - a rusted latch on the outside, a little corrosion on an outside steel plate, and really strange - the hinge under drop leaf dining table is rusted! Other than that though, it looks beautiful and I did some poking around in corners, ceilings, floors etc. Then I went on top of the roof and saw quite a bit of foam sealant. Didn't really think much of that until I got to thinking later - I wonder if all that sealant up top is how it comes from the factory. OR perhaps there was a water leak at one time and the dealership resealed everything.

We live in the rainy corner of the NW, and I suppose even a brand new rig just sitting on the dealership lot could have a roof leak. I have asked for - in writing - from the dealership for the truth and am waiting to hear back. Anyone out there have experience with what a new roof looks like - is there lots of visible sealant on top? (I searched images on the internet and really couldn't tell.)

Thanks in advance for experienced input!