Many famous brands use sunglasses as part of their product line. Many sunglasses manufacturers will also advertise the features and special qualities of their products. Depending on the characteristics and brand, the price of sunglasses will fluctuate between less than $20 and a few hundred dollars.
In addition, there will be counterfeit goods on the market. When you go to discount stores and flea markets, you will find that vendors sell counterfeit goods that mimic high-priced branded sunglasses. They look exactly the same, but the price is much lower than the real one. When you buy genuine branded sunglasses instead of counterfeit goods, do you spend a lot of money buying a brand, or is it really a fundamental difference?
The biggest problem with cheap sunglasses is the way the lenses are made. They simply plate a layer of colored film on plain plastic. Even though the colors and frames of these counterfeit goods are similar to some famous brands, the actual lenses are quite different.