Does Botox in the hairline treat anything other then reducing how much you sweat at that site?

Thank you for your question.  I often treat the forehead lines higher up in the forehead to diminish the chance of brow ptosis.  There are several different techniques to treat the forehead lines, and I will vary them depending on the physical exam and where I see the most movement and lines.

It's unlikely your physician is simply injecting extra Botox in unnecessary areas to charge you more.  Without being able to examine your hairline your forehead and hairline, it's difficult to make a definitive conclusion but it is possible that your hairline extends beyond the area of frontalis muscle activity.  This would necessitate some injections near the hairline to fully treat the lateral aspects of the muscle.

Thank you for your question.  Unfortunately without an in-person examination or photographs that demonstrate the type of wrinkling you have, it is difficult to be able to answer why your doctor places injections at your hairline. I would assume it is for dynamic forehead wrinkles that can be present near the hairline.  I would recommend you speak with your injector directly and have them explain to you their treatment plan used to gain your results.