All human lives are important and when one ends it is sad especially if the person is young and did not experience as much of life as they should have. Celebrities lives are as important as anyone else. Their deaths are to. When Robin Williams died that was very sad.
If by celebrities you mean famous people then yes, they can make a worldwide impact. I'll give some examples: Einstein, Hitler, JFK, John Lennon, Saddam Hussein, Steve Jobs, Martin Luther King, etc. Many of these figures had direct impacts on our lives or the lives of many others and their deaths are important.
Should we know about them? Sure. Should we care? Not really. We shouldn't disgrace and show no compassion for the families or the dead celebrity, but it isn't news. They're people. Some were druggies or alcoholics that took attention away from more important and newsworthy events (Cory Monteith, Amy Winehouse.), while some died of old age, or were murdered. So? Let the family grieve, we shouldn't care, since they didn't affect our lives, we didn't know them or anything. Even if they were your inspiration, you should show a simple gesture of disappointment and continue on with your life.
If I had died it wouldn't on the news headline, but when Michael Jackson died it was all over the news headlines. What difference does it make. You may say that they had a big influence, but I could of also changed the world while being poor. I think people judge it of how rich you are. Lets just wait until Paris Hilton's dog goes missing, I'm sure everyone will go nuts.
Instead of wasting paper on news articles of peoples death, change it to climate change and things that are very important. We have other important aspects in life.
Can anyone honestly believe the death of a fame hungry individual can in anyway be important when they finally pass away?
Sure its sad for their family, but if Kim Kardashian and her entire clan died tomorrow - would anyone apart from Hello magazine really care?
And if your one of those people who pays attention to what these media chasers wear so you can look similar - more fool you.