Don't ever use services provided by a third party. That's why I cut my own hair, make my own toothpaste, and create my own electricity from coal I mine myself!
Your comparison, and the toaster one by the responder, are nonsensical. There's a difference between a product and a service. Toothpaste is a product, not a service. AWS is a service, not a product. You can buy toothpaste anywhere; if you want to compare with AWS, AWS is like hiring a dental hygienist to come to your house twice a day and brush your teeth for you instead of doing it yourself. The hair-cutting bit is valid, but lots of people cut their own hair, especially men. The electricity bit is only partially valid; coal is a commodity that you can buy, just like toothpaste. You can also buy solar panels and make yourself totally independent of the electric utility. But it falls down because electric utilities are utilities and are regulated as such, whereas AWS is not regulated. The toaster thing is just dumb; toasters are cheap commodities. Again, the AWS comparison is hiring a butler to make your toast for you.