Why do people spend so much on costumes when Halloween is just for one night?

The stores have the costumes at outrageous prices and for half the cost they can make them and it will mean just as much to the kid as the ready made ones. Plus it saves money. Everyone now has a issue with money in one way or another and well i know the little guys and girls and even the big ones want to get the latest and coolest costumes . But my goodness folks it is only for one night and who cares what costume you are wearing , what matters is the candy right? And what about those that can not have candy due to a medical condition , don't you think they feel a little left out ? I like Halloween if it is done right meaning give every one a chance to enjoy safely. A church bizarre or fall festival includes everyone and it is a lot safer now a days than going door to door and or running across a busy street with traffic . Last year i saw a five yr old and his little sister not more than three just run across the street to a house and almost got hit by a truck , driving way too fast . I just knew they were going to get hurt or killed , luckily they got across and what were the parents doing, talking on cell phones and laughing it up like nothing at all. I was so mad, i pulled over and said do you realize how close your kids came to just getting hit by a truck and they admitted they were not paying attention and i said then get over there and make sure they get across safely because they may not be so lucky the second time, on this street they drive fast. They thanked me and i said next time get off the cell phone and pay attention. That was stupid .