Apache question

I guessed that would be the case, but my reading of shell scripts is less than ideal so couldn't figure out exactly how.

I believe the startup script is /usr/local/etc/rc.d/apache24 and I see

but don't see where this is passed as a parameter to apache.

I know it must be there, I just can't see where.
It is at this line:
apache24_flags="-f ${apache24_configfile} -c \"PidFile ${pidfile}\" ${apache24_flags}"
How stated in httpd(8):
-f config
Uses the directives in the file config on startup. If config
does not begin with a /, then it is taken to be a path relative
to the ServerRoot. The default is conf/httpd.conf.