If you’re improving your eyesight, you already figured out that most optic shops overcharge massively for glasses.
500% or higher markups on lenses, perfectly normal. Gouge-town, city limits.
Not entirely surprising if you already realized what a scheme the whole basis of modern optometry and myopia treatment is. So why go put more money in the pockets of those who caused your progressive myopia in the first place? Unless you find a supportive optometrist, who will help you with your goals, and give you eye-friendly corrections, you might as well save lots of money and shop online for glasses instead.
I posted a thread in the Facebook group, to get feedback on where students like to shop for glasses online.