

Left front phone. Right front knife or multitool. Coin pocket zippo. Rear right wallet, rear left key fob. On the occasion I have my keys me, they’re on a short leather strap clipped to my belt loop in my right front.
Due to my job, all my jackets have a millimeter ruler and a staedler 319f marker in the front pocket, and my left inside pocket has a fountain pen with blue ink, and a pilot gtec C4 with black ink. Right Inside pocket has a hairtie, toothpicks, and a carved jade turtle figurine (skjoldpada).

Because hair color isn’t homogeneous. Every hair is a slightly different color, and it’s significantly more noticeable in lighter hair. Blonde hairs are predominantly gold, but range from white to brown. In cartoons, gold is also usually just yellow, because animating something metallic is a pain in the ass. Hair is shiny as well, so they picked the average color and called it good enough. Grey hair is the same way.
As for only existing in humans, that’s just not true. Yellow labs and golden retrievers come to mind immediately, and plenty of rodents are blonde. While those are fur, not necessarily hair, golden doodles have hair, and are usually some manner of blonde. Golden macaques, flying squirrels, lions, etc.