I don't know why they put some stickers on that are impossible to get off.
Many years ago I got a new set of tires and one of them had a very slow leak. Took it back to where I bought it and three different guys checked it and couldn't find the leak. Finally an old timer that worked there said he thought he knew where the problem was. For whatever reason the tire manufactures put the bar code stickers on the inside rim of the tire and they can cause a leak. He worked his magic and fixed the leak.