Why motocycle tire label rear/front?

I'm a bit confused I was shopping for tires for ma Honda SH150 Scooter. All the tires I found are labeled front or rear and they do not come in pairs. Very confusing. I've always bought car tires with no such issues. Can I just buy two tires of the recommended size. And not worry about the front/rear thing… Help

The tread is shaped differently front and rear. The front tire has the tread grooved so it throws rainwater to the sides and not so much up off the front of the tire where it will come back in your face. The rear tire is also shaped for not only the water but also for as much traction as possible for the power-train.
They don't come in pairs because the front does not wear as quickly as the rear.
You'll understand more you ride.

Nice scoot, does over 65 mph on the freeways, legally anywhere in the US
BIG wheels: Tires: 100/80-16 (front), 120/80-16 (rear).
My Vespa has 12K+ miles, still on the original front, am on my third tire on the rear.
It is common for having different brands of tires front / rear.
If you want to ride in winter, you can get Heidenau Snowtex tires.

Motorcycles are not cars. Look closely and you'll see. Front / rear specific tires are a fact of motorcycling.