Having some people cheat their way around it does not invalidate the law in the first place and neither does it invalidate its intention. The equivalent in Uber

Having some people cheat their way around it does not invalidate the law in the first place and neither does it invalidate its intention. The equivalent in Uber's system is a driver cancelling a ride after accepting it and seeing the destination, maybe claiming his car broke down on the way to the pickup location or whatever. The fact that people can pull that off also does not invalidate Uber's original attempt to make drivers accept riders regardless of their destination.