Just like any shape and/or geometry in general they are very important. Regardless of what you will ultimately study they can be used in many normal life scenarios. Since everything in our world is a shape you may need to calculate if something may fit somewhere, or if a certain fence can be made a certain way. This also applies to parallelograms, maybe you are trying to build a cabinet that will go in the corner, but the corner is not a 90 degree angle, knowing parallelograms and geometry can help you design and build the best cabinet.
