Many moons ago a friend of mine bought a ford van with a 302 in it- it used quite a bit of oil right out of the box. Ford told him if it used a quart every 800 miles or more it was normal...
I had a 91 Mazda (jap engine) that used a quart every 2500 miles, I was doing 3000 mile changes. I switched to synthetic, same brand, same weight, and it went 6500 before needing a quart. I went to 8000 mile changes because the oil was still clean looking until then. That really doesn't make sense why it did that but it did. 1/2 quart in 3600 is fine. If it gets dirty really quickly it could be a sign of blowby/ring wear. Still not a big deal. Pour oil in it and ride.