1 quart in 1k is "normal" dang.... I first replaced them at 50, then 90, now I'm changing them ever 25k because they are getting bad, that is why I'm going to replace the valve gasket again. I think I did that at either 90 or 105k, I don't recall, I just remember it wasn't fun. Right now it's missing so I replaced the plugs on Monday now it's misfiring on 3 cylinder so I ordered a coil pack. Just this engine has been a ton of work and like I say I really don't trust it anymore, I'm probably adding 1qt every other fill up and I usually fill up at 1/4 tank...
So that is less than that is "normal". If I can find a block from a '16, I wouldn't mind spending the time fixing that one up... I have a friend that got an '18 Outback for $1,200 and gets deals like that all the time. It's totaled but for that price it didn't seem like a lot of work other than the rear end....
I've been buying a lot of oil, I believe it is the pistons going bad, I replaced my harmonic and all the pulleys because they aren't like how they should be and another guy told me the harmonic is in line with the pistons and if the pistons aren't shooting straight they throw off the harmonic if I recall correctly...
We get feet of snow and love the way it drives in the snow, i am really just disappointed with both Subaru Service centers in my area, I had told them several times and they never "officially" documented it even when I paid one of them $160 to pour UV oil in there and tell me it wasn't leaking. I knew it wasn't leaking because it's burning...