I think it makes complete sense to measure the distance to something in terms of the time taken to get there, and in most cases this is what other people really want to know.
There is a big difference between something that is 5 miles away though a busy downtown area and 5 miles away on a highway. When you tell someone how far away the park is from your house, they don't really care whether it is 2 miles or 5 miles away, but they do care about whether it will take 2 minutes or 30 minutes to get there.
Astronomers and physicists also measure distances in light years!
This is totally standard and very common practice.