Do you ever see something in a movie that doesn't stand out as wrong or nonsensical but once it's pointed out you sit there and say how could I have missed that. Now in interest of full disclosure I've been accused more then once of being over analytical and there are right.
So here's my question, Take a look at any old or even newer western movies. You have the classic town with rough saw wooden building, hitching rails in front, watering troughs for the horses. They also will make cover when the gunfight breaks out. So there's your setting. Now in the 90 or more odd years of making westerns, anybody ever seen a person fill those troughs. A few will have a pump attached, but most are free standing in a arid climate with no water system attached. But they are always full??????? Hmmm! Go ahead, watch an old western on late night TV and see if that question doesn't pop up in the back of your mind now?
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Yeah these are the big questions the world is seeking the answers to!
Now don't get rowdy, just having fun.