Dark Matter

I always thought the theory of dark matter was sketchy. It reminded me of the theory of "Ether" from 100s of years before. Just because our measurements for mass doesn't add up in our calculations for this universe someone, just said, oh well something has to be there to make the calculations correct so they invented "dark matter" out of thin air. That's the first big sign as to why that theory may be bunk. Don't get me wrong there may indeed be something akin to dark matter but the way the theory came to existence almost seems like a cop out. Although, I like what Tyson said about labeling it as "dark gravity" which would make more sense to me. Then again all of this could be a computer simulation and all of it doesn't "matter."