Reading adverts and copy as I do, I've noticed that spelling is not high on the priority list for most businesses.
The latest villain in this litany of uselessness is "loose". Loose weight now. You have nothing to loose. Are you loosing your mind and so on. You obviously know that it should be "lose".
The problem with spelling mistakes and grammatical errors is that it indicates that your company has sloppy thinking, no eye for detail and a cavalier attitude. Imagine if someone read one of your proposals and it was littered with spelling mistakes. What would be your thought process if you got a sloppy piece of work? "If they can't even get their proposal right, how are they going to get my business right?"
God and the devil are in the details. Focus on the detail so that you can get more business.