Angenoir that story is so so sad. That lady probably walks around thinking she just has fine hair, too. and is addicted to sew ins because it's the only way she thinks she can have full "healthy looking" hair.
How did you keep from talking to her? I would have found a reason to get her number. I'd have told her I thought I saw a deal on the hair I was wearing (since she wanted a similar install) but to give me her number and I'd let her know. I would have found a way to fill her in on appropriate hair care so stylists could stop murdering her hair.