When I had a 50t ring, I only ever used it once, on a 15 mile ride with a heavy tail wind. I found that the smallest gear was too high for my style of riding, which includes very teel (20%) hills, and riding tracks and trails. Swapping the road triple to an MTB triple was one of the best moves I made.
With low gears, a standard touring bike can go anywhere a mountainbike can.