The story below is encouraging. It shows that money spent on infrastructure can be worth it. Also, sometime's it's hard to gauge demand for a feature like a bridge until you build it, and then you find it's well used (thinking about a potential Bow River crossing on the side of the CPR railway bridge at Nose Creek...).
Anyway, recently a bike/ped bridge was built in Charlotte, NC and it has made quite a difference. Thinking about Calgary, we'd probably agree that the bike/ped bridge at Crowchild Trail has been a huge benefit. Thanks to the anonymous benefactor that came forward with the donation that helped make it happen.
Where else do we need infrastructure in Calgary?