Why we learn compiler?

I am learning compiler in my Uni. I have been through all major compiler techniques like top-down parsing, bottom-up parsing, Lexical analyzer, Symbol table, etc. I have a good understanding of them, but I am still confused about the course.

What is the point of learning all these things? What are their applications? Where we use them? The main point is, if someone asks me, Why Compiler? What is the benefit of taking this course?