You are lucky to make a profit by doing that because it need more research to check if the project is good or bad. It is not easy to find the right coin that want to listed in the exchange.

But if you want to participate in many new projects, that will cost you much money. Not many people can have a lot sources so they will twice before decide. I prefer to research the coin/token that have movement so I can check the detail.

If people want to follow what @Op did, they need to learn and practice and that will need time. It is better to research what is the best way that works for us so we can focus to learn that.