Back in the day, and even earlier, British bikes have always been accepted by most groups of Americans. When I rode my Norton to Sturgis in 1975 I spent a lot of time hanging out with a 1% organization and was accepted quite well even though I was riding British iron. It was the guys on Japanese and other to a lesser extent the Italian bikes that were derided by the small group I hung out with.
Besides, do we really care what other people think about our ride? I figure if you have the disposable income and really like the way overpriced American iron then go for it, it you want a quality bike at a reasonable price, look elsewhere.
The fact there are still so few Triumphs (relatively speaking) in the US makes you more of a visionary and leader among bikers, rather than being looked down on.
bob