This thread kinda sucks. But I guess I will answer it anyway.
Recent college grads are underemployed because they are either lazy, in a field that is extremely competitive or their job was shipped overseas. I'm betting that it's a combination of two of these cases, most likely lazy and extreme job competition.
I graduated with a double major in accounting and finance. My first year out I worked in Manhattan at a top 5 financial institution. After 1 year I quit and taught myself software development, and have been in this field ever since. I now manage an entire software development team and directly report to the CEO. I worked my ass off to get where I am. "You" are underemployed because you are lazy and not as smart or competitive as the next guy who wants your job.