There are some brands of bicycles that can cost more than the down payment on a car. Why? Surely making a bike lightweight and reliable isn’t so difficult that it warrants that price? Is it just the brand name or maybe it has to do with customization options?
For a lot of people the point of a hobby seems to be as an outlet for their unhealthy relationship with money and purchasing, and markets find ways to take advantage of that.
You can buy good used bikes for cheap though, and maintain them cheaply also, so it isn’t a problem for people who are not stupidly rich or insane.