I would say that getting good grades is quite a big deal.
I have had a very good GPA throughout my academic life, I graduated in the top 25% of my class last May, and now that I'm in college I am reaping my the sweet fruits of my hard work.
I can go into practically any college I want without my resume being in question, school is going great for me, and I am eligible for many scholarships.
It's amazing what shedding sweat, blood, and tears or something can do for you in the end. The process is indeed painful , but the rewards are more than worth the effort.