Problem: Quick and easy shoe changes, sans the constant ungraceful process of retrieving the heels from the plastic bag.
Solution: A repurposed promotional tote bag is sturdy enough to withstand heel puncture and lays neatly (and quietly) inside your bag.

I often find that it's impossible (especially in the winter) to do quick shoe changes in New York. There's always a cumbersome situation--unwrapping a plastic bag, pulling out your heels, switching out the shoes and then shoving it back in your bag.All the while, stuff's flying out.
So....since I had an old promotional tote bag lying around....

I cut down the two side seams, cut off one of the straps, and folded one side into itself. Leave one strap still attached, so you can easily grab it from the bag abyss, unflap the fold and gracefully grab your shoes out. The things we NY girls do.