Is it illegal to use pennies as flooring?

Is it truly illegal to use pennies as flooring in a home or business? I've heard rumors that the practice could be breaking the law, but I'm not sure if there's any truth to it. Are there specific regulations in place that prohibit the use of pennies in this manner? If so, what are the potential consequences for those who choose to ignore these rules? I'm curious to know if this unique flooring idea is feasible or if it's better to stick with traditional materials.