Hosting Landing Page AWS vs. my website

Hello, I'm just starting in CPA marketing, already got accepted in a couple of networks, and about to set up my first campaign. My question is about hosting landing pages.

I see a lot of people talking about hosting on AWS. Since I already have a website built for acceptance into CPA networks, I can just upload my landing page into a subfolder on the site e.g. http://www.mydomain.com/landingpage. What are the benefits of hosting on dedicated services like AWS vs hosting on my domain?