If you are of the lower castes, and a higher ranking child says this to you with his hand outstretched and welcoming, run. Run away.
The best you can expect is a crushing handshake.
But it's rarely a lone wolf attack - to risk approaching someone as unpopular as you, there's usually going to be a bigger payoff. Chances are you'll be held in place while others come to laugh at the fact you dared to want or expect friendship. Often, there is violence.
Finally, the crowd will be overjoyed if the injustice causes you to howl "you liiiiiiiiiiieeeeeeeeed" before losing conscousness. They know they lied. That was the whole point. No wonder you get picked on.