Paper and Framing GRIPES

I am just feeling so frustrated, and I know that all of us who frame artwork feel it everytime we go to frame something. Why cant the frames be the size of the paper or why can't the paper come in the standard size of frames. Does this irk anyone else!! I think its a ploy by the custom framers of the world to drive us crazy. Either my painting is too big, too small or misshaped to fit in the standard. The brahma bull needs to be enlarged to fit into the a standard 16x20 mat, or I have to spend tons of money customizing sizes. UuuRRRRGGGG. Luckly I have room to expand the painting but it will change the compostition too. The lemons and limes is right to the edge so I didn't have room to expand, but I did crop, but since mats don't come big enough I still had to custom cut them. I need to master my mat cutter!