During the initial days people started using it for some purpose. Most of them say it is for gambling and darknet needs. By that time the real users well understood about the technology and the good about it. Later the usage started to increase as a result of its increase in price. If bitcoin haven't gained good price in the market, surely this couldn't have reached the present level of growth through the people understanding the goodness of its underlying technology.
Bitcoin was originally developed as a P2P payment system. Due to the development of current technology, its use has greatly increased, which has led to an increase in its price, with the increase in price, people are considering it as a resource. So people from different professions are investing in it. Regardless of the price of Bitcoin I think the original purpose of its creation has been successful.