I’ve struggled over the years with artists who steal from other artists and purport to call their work original. I will never endorse people who steal ideas from other people and turn a profit. The age of piracy and duplication concerns me.
As the original author of a piece of work, you feel robbed. And you should. But that’s the glass half empty view. If people are copying you, that means you’re worth copying. Take pride in that. Many of my wisest mentors always carried a delicate smile when they declared piracy of their IP because it affirmed that people care. If your work is being stolen, find a way to take advantage of that. Other people are marketing your work for you. That’s a good thing. Use it.