First, I am not a person who uses professionals to enhance my skin, hair, nails, or whatever. I use professionals to keep me healthy. They are expensive and somewhat budgeted. I can't imagine dropping $80 on an eyelash!
Second, google eyelash extensions. Wow! Apparently, this practice of wanting fancier eyelashes has been around for centuries. Not sure why I am surprised. Making oneself look better has been a thing since time started! However, I can see where the cost comes in. If a person who isn't trained properly grafts or affixes synthetics, silk, or other hairs into your eyelids, you chance infection and losing all your lashes.
No matter, having to spend $160 a month for fancy lashes seems a bit risky anyway. It is all a matter of choice and for me, I'd take those funds and buy books, drive to visit friends, or buy some fun lingerie!