> Predators even don't like the sun in their eyes, that's why they attack with sun behind them, if they can.

While I have no doubt that predators don't like having the sun in their eyes, they would obviously still prefer to attack with the sun behind them even if they didn't care. It's very advantageous, because the prey doesn't like having the sun in its eyes.

Attacking with the sun behind you is to prey with eyes what attacking from downwind is to prey with noses.