Sexist or not?

I work in a sewing factory in my small hometown. There are only about 20 employees and the business has been family owned for over 40 years. I started in August of 2014 (2 years ago in just 3 months). Currently, all of the employees are women except for 2 men. They started me sewing and I absolutely loved it! About 3 months ago, my boss told me that he was moving me to the cutting department because one of the people that was in that area quit. There was only one person left over there and that is my uncle who has worked there for over 3 years. He started at $7.50 an hour because of the cutting department being more stressful. After not missing any work and after all this time, he now makes $9.50 because he is head of that area. All the sewers make $7.25 an hour which is minimum wage with no chance of getting a raise. I never got bumped up to $7.50 an hour due to my boss stating that he wanted to move me between sewing and cutting when needed. 3 months later, I still am just in cutting with no raise. Yesterday, a new guy was hired to help in cutting with no prior knowledge or experience. He mentioned that he thought it was great that we start at $9.00 an hour and was wondering if we get regular raises or anything. All of us just looked at him. One of my coworkers who has been there for 20 years said, no the men make more money, the women make minimum wage. I got an interview this afternoon at another job wanting me to start immediately tomorrow. They start at $8.25. I accepted and will have to tell my current job in the morning that I'm sorry I can't give a notice but I quit. Does anyone else think that it's sexist for the two men to make more money, especially the one who just started with no knowledge or experience, when I have been there for almost 2 years and do exactly what they do? I lift heavy rolls of material, I find patterns and use them, I do everything they do and never ask for their help.