Hale wrote...
I prefer a story/campaign because of the adventure it holds. Even if it's linear with not much replay value, there is still a story to be told and an adventure to experience at least once. Great cinematic moments can be crafted in a story driven environment and these moments are the reason I play games. When that mixture of great voice acting, storytelling, artwork, and music can trigger any emotion that it was designed to.
For online gaming it depends on the type of game but from my experience it has become way too competitive and way less fun over the years. Now I have my share of stories of great underdog victories and epic comebacks just as anyone else does, but it isn't worth the competitive and stressful atmosphere in my opinion. Maybe some folks like the challenge of competing against other humans, but it's not where I find my fun.
That being said, I really enjoy a good online co-op campaign. When it becomes less about competing against another human and more about cooperation with friends (and sometimes strangers) and where we can play at our own pace and progress through a story together.
I agree with everything you have said. The fun kind of dims when it comes to online gaming as you have the competitors fighting to be the best. Gaming with friends is a laugh; the infinite teamwork and arguments with people from around the world, which is a pro of online gaming - you get to play with people from around the world.
edit: However, with that said, a story in a game can become extremely gripping, and when you finally complete it you will play it through again. When I received Final Fantasy XIII I played it for around 16 hours on the Saturday, and about the same on the Sunday. I had a lot of free time ^-^