Why does "systemctl restart xinetd" kill all processes that can trace their ancestry through xinetd?

Issue

• The command "systemctl restart xinetd" will not only restart xinetd, but in the process will also kill all processes that xinetd spawned, and all the processes that those processes spawn, and so on, ad infinitum (like telnet login sessions if in.telnetd is being managed via xinetd).

• The "service xinetd restart" command will terminate the user login session ( rsh, rlogin, telnet) on RHEL 7 host.