Yemeni jambiya and Omani khanjar fake rivets

[Kubur]

Hi Guys

Can someone explain why Omani khanjar and Yemeni jambiya have fake rivets?
Rivets go through the hilt but they don't fix the short tang of the blade.

I can see 4 explanations

1/ In the past jambia had long tangs going all along the hilt
2/ In the past jambiya had hilts or grips made of two parts
3/ The rivets are just practical, to assure a good position of the hand
4/ A combinaison of two of the three above

Any solid clue???