Are you meant to be embarrassed to ride a mtb on the road? Nobody told me! I've been riding a mtb for the past 15/20 years and very rarely did any actual mountain biking on dirt trails. Even did some long rides to Hell on a very heavy old mtb. Didn't occur to me that that could be a problem......Why should you care what anyone else thinks? The main point is to have a bike that is comfortable and fun to ride. And I for one can not afford to have three or four different bikes depending on the ride. That wouldn't work anyway as I may change my mind half way through the ride and head up a trail instead of staying on the road. So I say, go out on you mtb and have fun!