A few days ago I implied not everything unixy stores 
the home directories in /home oh github [0]. Then I 
wondered why I have seen both /home and /usr/home on 
FreeBSD systems and took a look into `hier(7)'

The only $HOME mentioned in the manpage is /root,
no /home or /usr/home. The most useful information
I found is a mailinglist thread discussing the 
difference [1].
From what I've understood /home is/was used as a 
mount point when there's a separate partition for 
the users' home directories. When there's no such 
partition it's symlink to /usr/home assuming /usr
has it's own partition thus the users' home 
directories won't clutter the root filesystem.

I'm not 100% sure that's correct. A recent 10.2
installation on ZFS created a separate filesystem 
for the home directories but it's mounted under 
/usr/home and /home is a symlink pointing there.

PS: Affects only those people who actually read
    `hier(7)' ;)

[0] https://github.com/saltstack-formulas/users-formula/pull/100#issuecomment-156350893
[1] http://freebsd.1045724.n5.nabble.com/usr-home-vs-home-td5012063.html