Jack's leadership style is that of a tyrant. So, the idea of him wanting rules does seem a little strange. Here are the words that demosntrate Jack making his request. There are some clues in his tone and his thoughts:
“We’ll have rules!” he cried excitedly. “Lots of rules! Then when anyone breaks ’em–"
Jack seemed to look forward to the opportunity to punish others. This must have been exciting to him. He must have a violent streak in him.
This violent streak is already apparent in his struggle to deal with the present authority in Ralph. Jack himself does not want to be bound to or accountable to another man. The person who is not willing to submit to a higher authority is often not willing to obey rules. Therefore, it is ironic that Jack would be excited about them.