I think a lot of dancers want to find their niche’ in the market and that’s a very wise thing to do for business. In saying that however, you have to realize that although you may have worked hard to come up with a new concept or fusion, quite possibly, some others may have come to the same concept as you and (shock and horror!) they didn’t even copy you to get to it.
My advice is just be bloody good at what you do. That way if someone else does something similar (or that you think is similar) it won’t threaten you or make you feel insecure. You can actually share in the joy of having a common passion or that maybe great minds think alike.
Secondly, don’t go out of you way to tell them they’re unprofessional for stealing your style when said person has never seen you perform. THAT would be a rather challenging thing to do. Obviously, there are things that are stealing such as creating a ‘SQNY’ sound system instead of a ‘SONY’ one, or copying someone’s tagline or deliberately trying to elbow in on their clients. Those things are wrong, but someone having a similar style of dance; very hard to copyright. Two Spanish Dance schools could accuse each other of copying them, or someone who adds a new prop to a well-loved dance form such as silk fan veils to belly dance would have to stop everyone else from doing the same thing.
All that to say, good people, be original, try new things, discover but then rather than trying to stop anyone else from being like you (whether real or imagined) just be good enough that you’re confident in what YOU have to offer, keep learning and growing and network with those who are like-minded rather than making them your competition. You never know what opportunities you may miss out on by pushing people away with your pettiness.