SMB Share automatically created dataset for user?

[erezz]

Hey,
I created a dataset for SMB use, created a share with permissions, i can copy files and it seems to work well.
Later i saw that it simply created a dataset as a child for the parent dataset share, that dataset is named after the user which create the files and folders automatically.
I can see that it claims space, i could not find any explanation for this beavhiour.
am i missing anything?

Thanks