Description of Problem: There are too many situations when such test may give both false positive and false negative results for this thing to be reliable. True, an installation has to be modified for that but this may happen and why create weird surprises? [ "$(id -u)" = 0 ] || exit 1 should do the job instead. This bug shows up also, at least, in initscripts-6.67-1 used in RH 7.3 distro. See also #76612 for a related gotcha.
initscripts are part of the particular package.
This was fixed in xinetd-2.3.11-1.8.0