Seeing "1%" or "2%" on the lower-fat milks suggests a lot of fat has been taken out -- you might even naively think 98%+ of the original fat content. But in fact 'whole' milk is only 3.25-3.5% fat -- not much difference.

And, the process for creating 1% or 2% varieties involves stripping all the fat out -- taking out other things as well -- then building the milk back up to the desired fat/vitamin/milk-solid levels with additives.