Yeah, these reflect Snowflake's staging options:
https://docs.snowflake.com/en/user-guide/data-load-overview.html#supported-file-locations
What you choose really depends on your requirements. Internal stages make sense for most users, they're easier for a few reasons particularly that you don't have to manage the extra credentials etc and yes the data would transit an extra hop back to AWS. But if you need to access or audit the staged files, S3 or another cloud storage provider would make that a lot easier since they usually have a feature to auto archive whatever data had been stored there.