Yah, I get it, makes sense. Personally for me I've spoken to people who have called me about it and I look back at their card usage history and I can see that they have been using a credit card in my bays for 3 or 4 years and never noticed until just this last time. And also I've spoken to other people who have used their card in my bays for years and never even noticed or knew the whole pre auth thing ever took place. On the flip side, I've had many people who will now quit using their card all together and just use cash once they find out about the whole pre auth thing, they just don't trust 100% that the amount will change, it's just more complex and more chance for something to go wrong than the average credit card transaction at a retail store.
Given all this information, my point is that I don't want to draw attention and throw a big red flag out and alert all of the people who never even notice that this happens, because I guarantee that a sign like that will make some people choose not to use their card and just use cash.
