I know that Nginx does not support .htaccess files, but if you used Nginx as a reverse proxy (is that the correct term, Nginx handles static, Apache handles dynamic) with Apache, would you be able to use .htaccess files then?
If you use Nginx as a reverse proxy to Apache, then Nginx is "passing along" requests to Apache on behalf of the end client and delivering the responses back to the client. Think of it as a man-in-the-middle sort of situation (because it is).
If you configure Nginx to serve static files, then it will do just that... whether or not you have any "wishful thinking" rules in the ht-access file. It doesn't know anything about ht-access, Apache does. On the other hand, for any requests that Nginx passes on to Apache, well... Apache is going to act like it always does.