OMG Janet - I never had long legs but there was no way my mother was going to buy me long-enough pants if last year's pair still fit in the waist, so I too cannot bear the sense of wearing pants too short.
My little bro talks about being shamed for wearing a boys' "husky" size, not because Mom felt boys should be thin (that was for girls) but because the husky size cost more.
I have spoken before about also wearing endless hand-me-downs from a girl cousin who was 3 years older and 6 sizes larger. And tall.
Believe me, I am 100% sympathetic to the issues involved in raising children on a tiny budget. I am also 100% sympathetic to children wanting to feel comfortable, accepted, and as if they have something of a say in how they look.
Little husky bro got sent to Catholic school for one year (age 9) and used to come to me daily in tears because he had - again - misplaced his clip-on tie.
Whatever my other failings as a parent, I know I never browbeat my son into wearing anything that was stressful for him. If he wanted something beyond my (tiny) budget, the rule was I would provide what the budget version cost and he would save up and kick in the delta. Worked for us.