Assuming access to quality foods, but activity and metabolism keep them skinny (that is, this is a healthy skinny, not a malnourished skinny), in what ways are below-average weight people's quality of life sacrificed?
That's fair, but in my experience (from when I was fat), buying clothes that fit may not have been hard. But buying clothes that fit and looked good was hard. They even have specialty shops for the particularly obese, it's not like they're finding well-fitting suits off the rack at Jos. A. Banks.
EDIT: Actually, clothes that fit could be hard. I wasn't terribly round, I ended up with a 38" waist at my fattest at 5' 10", but usually around a 36" waist. But my legs, thighs in particular, were not toned or thin. My option on pants almost always required me to go up several inches on the waist to get pants with large enough legs for me. My thighs, now, are well-muscled and toned, but I still have a hard time finding pants that fit them well now that I'm down to a 32" waist.
But I still don't think the problem is catering to the obese hurting the skinny. The problem is that being that thin is abnormal (from a statistical perspective). Consequently, it's a small market. It's hard to justify making off-the-rack shirts that fit a 6'2" 120lb man. Just as it's hard to justify making of-the-rack shirts that fit a 5'4" 250lb man.
