There were innumerable inconveniences suffered by the american people during WWII. It doesn't compare to the citizens of the oppressed nations the Allied powers would ultimately defeat. That aside, the food and gas shortages, and overall reduced services from local businesses combined to make what might have been normal life (for a post depression society) even more bleak.
When the finally ended it wouldn't be "all back to normal" for a while. In the mean time, businesses had to do what ever they could to let customers know that they were making progress. This original poster I found likely hung in the window of a hotel in the most visible spot. It is an awesome find!