Using different domains reduces attack surface area [1]. That said, I agree that the blogspot domain and site design look amateurish.
[1] https://github.com/blog/1466-yummy-cookies-across-domains
[1] https://github.com/blog/1466-yummy-cookies-across-domains
> If we receive a removal request that violates local law, that content may no longer be available to readers on local domains where those laws apply.