There were no McDonald's in the area of NY I grew up in. We ate out whenever we went downtown to see a show, which might be a few times a year. Other than this, we ate at home or at relatives. But it wasn't until I was in HS that a McDonald's opened near us. My parents did not see it as a treat. They knew it as "junk food". I remember liking the french fries and buying them for myself when I got a babysitting job.
Today so many kids live on that stuff. It is not nutritious, and I am even guilty of stopping there or Wendy's on our many baseball nights. I do try and get my son to order a baked potato and chicken and I like a salad and fries. I know all that grease is terrible for us.
But yes, to answer the original qustion, I did see those fries I ate in HS as a treat.