It seems an extravagance to me - we don't have the weather to be able to use them more than 3 months out of the year, and the rest of the 9 months of the year, they just cause traffic problems and are a waste of valuable space.
I use my bike as my main form of transportation from early April to the first big snow in November every year---typically eight months a year.
In Winnipeg, the separated bike lanes can be easily removed in the winter to facilitate snow clearing, but some of them are in place year-round because there are a lot of crazy winter cyclists and they remain well used.