not so much because it depends on the way you or which product you are using for the promotion by using online marketing,it is true that it is effective and have good results also but it totally depends on the way you are using it.
if we talk worldwide then i muswt say everyone don't have access to internet or computers, moreover if you want to reach out to billions of people the best would be advertising through print media or TV ads. but however if you cannot spend that much then go for online marketing, email marketing or PPC which mainly targets your Internet users.
It's a mix of online marketing and other stuff! You can't do just one thing. Walmart, Mcdonlds are brands. If tomorrow you invest $1 billion dollars in something and you advertise it very well, I think you will have the same bubble or become as much as popular like them!
Yes if you are not a brand name. To promote any website internet marketing is only the way to get the millions of the visitors or viewers on the website. There are two type of task are come under internet marketing. One is the SEO that provide organic traffic to the website. This is a time consumption work. Second is PPC that provide a instant traffic that are provided by the Google adds technology. This need much money for regular bases. So any how we have to take the support of internet marketing for gaining traffic on a business website.