With /lib/gentoo/functions.sh, messages are always sent to syslog via the logger utility. With /etc/init.d/functions.sh, messages are only sent to syslog if the EINFO_LOG environment variable is set. See the elogv function in libeinfo.c. I don't think we need to send messages to syslog most of the time, so the openrc behavior is preferable.
This is fixed in 0.3.