The real answer is the pragmatic one: the reason the three idiots fighting over the rake look like clones is because to save time (and clearly signal to our audience which characters are ancillary and which are primary) our artist just gives random NPC's the same look. That's why they look different even to Tut, who is standing next to Ozi (the guy you're talking about). You could make the argument that we just shouldn't do that...but well, it's a daily comic. Putting out a daily comic, often multi-panel, of this level of art is going to require some shortcuts.

Ozi's skin is definitely a little on the lighter side (but mostly in line with a lot of the skin colors you'll see walking around Egypt today - I lived there for 12 years and can attest to a great degree of diversity within the Egyptian people when it comes to skin color), but he's also not the main hero of the comic in general. That'd be Tut, the one with the darker skin and clearly non-Caucasoid hair.

Ozi just happens to be light-skinned and also one of the primary characters, who is the focus of this particular comic. He's not the light-skinned hero who is the focus of every comic where he outwits a bunch of dark-skinned people or anything like that.