I switched to adduser. The home account is still created.
root@svr-2004:~# adduser --no-create-home junk_acct
Adding user `junk_acct' ...
Adding new group `junk_acct' (1004) ...
Adding new user `junk_acct' (1004) with group `junk_acct' ...
Not creating home directory `/home/junk_acct'.
The...
It appears the -M / --no-create-home switch does not prevent the creation of the home directory as can be seen in the command line text below.
The useradd man page clearly states the following:
-M, --no-create-home Do not create the user's home directory, even if the system wide setting from...