This old argument again???
The difference between Amazon putting companies out of business and say Barnes and Noble is that Barnes and Noble had major competition back in the day with other big book stores. As an online retailer Amazon has very little to zero.
I buy very little from Amazon. There really is no longer a benefit from buying from them. If I do buy something from them it's only because I can't find it at physical retailers. I also pay either the same or less (most of the time) than I can get it at Amazon and I don't have to wait for it in the mail and returns are extremely easy and fast with physical stores. If it was a bit cheaper at Amazon, the savings isn't worth the hassle. So there isn't much incentive for me to buy from them.