The importance of certificates vary from country to country. Any business card I got from Germany or Japan would be loaded with any certificates or titles the person had. Many jobs would be available only if you were able to show the necessary certification.
In the U.S., it's somewhat looser. A college degree doesn't necessarily mean that you can do the job well, but at the very least it shows you had the discipline and intelligence to obtain it.
The are many exceptions - Bill Gates never finished college, if my memory serves me right. But, all other things being equal, if I am interviewing somebody for a computer job, a degree in computer science would impress me far more than just a high-school diploma.
Also, if someone didn't have any experience with, say Oracle database, I would expect him to show me at least some certification that he had at least learned the basics.