If you went to the EITF and said some people are passing payload data in the VLANID field of TCPIP packets they would laugh and call them an idiot for doing that. If you said that proved we needed to completely remove the size limit from the payload field of packets they'd laugh and call you an idiot. If you screamed censorship because they didn't give you your way they'd tell you to make sure the door hit you in the ass on your way out. They'd be right. There is a field for passing whatever data you want. It has a limit for perfectly reasonable technical reasons. We raise it as hardware improves but 9216 is fine for now. If we make it unlimited the price of networking hardware would be too much and too many people would be excluded from the internet.