I've seen that too. I have also been in mosques for business meetings. I had to cover my head, remove my shoes, and only speak if spoken to. Very hard to interact in a business meeting in that fashion.
And the lack of interactive conversation from muslims on this topic DOESN'T HELP.
If it wasn't for all the stories I was told from my family about growing up in a regime....I don't think I would be this patient on waiting for answers. Especially since I had family in the towers and have been to ground zero during clean up.
Was this not enough to give you clarity?