Coins = weight, and in a BOB that weight might better be used for something else. I am not aware that of your bug out situation, but mine is hurricane-related. Most vending machines will not be working in the wake of power failures caused by hurricances. Additionally, I have not encountered a modern vending machine without a bill changer. The new dollar coins will appear strange to most people (not many in circulation) and may not be accepted as legal tender in an emergency situation. Vending machines may also not be calibrated to accept them.

In short, you are likely much better off with a good assortment of paper money. YMMV

Craig.