Because others do not know when your business is not their business. Jealously. It's your money, do what you want. If you are sure you are gonna get into this sport, congratulations.
I took a risk when I bought my dive gear. A new sport. I was going to have the best gear I could afford. same goes for cycling. Don't want cheapo stuff when your life depends upon it. (Scuba.)
Don't let others bully you. Buy the gear you need, based on your needs.