Well shoot. If Subaru's come from the factory with defective lugs, then I apologize for making assumptions. It would have helped if you explained that in the beginning, but that is still no excuse for me passing judgement. My bad.
I learn something new about Subaru's every day. In a recent thread I was schooled that media/internet amplification over-exaggerates Subaru issues. No reason to avoid buying Subaru for an easily remedied lug problem if one likes every thing else about the vehicle.
To answer your question regarding wheel maintenance, to me it means taking them off several times a year (rotations in my case) and giving the entire system a going over. Clean, inspect, lube (if applicable), etc.. This prevents wheels seizing to hubs, calipers seizing, pads wearing down to metal, etc.. Especially important in the rust belt.