.....why is /ping disabled...?

 

It is to prevent users from abusing the command in some ways.

 

You can still "use" it just fine to check your ping, just not to abuse it anymore. Just type /ping and wait for the response. "You don't have permission to use this command." It's essentially the same thing, just a different message. (Although, you really could do this with any command. You could type /njdfsgbkdsgkjd and get the same result. xD)

 

/lo also works for checking ping