"Most high end equipment buyers I think would expect it! "

Maybe not. Most high end buyers understand the problems and limits of high end gear.
In fact with most things, the higher the standard the more maintenance is required. Ask anyone that has a Rolex , a Ferrari or a racing yacht...(the more expensive your spinnaker is , the more often you will need to replace it. People think that a $500 Cuben tent is expensive, yet Cuben spinnakers costing 100x that are replaced after a few races because they go out of shape or rip the first time in use)

But about tents, the high end Biblers, Integral Design,Stephensons,Lightwave (for example...) all need to be sealed.

But my point was simply to explain why that is so , not to justify it.
Franco