I'm adopting this package. This issue will be resolved by splitting the binaries, exit hooks and manual pages into dhcpcd-base (provides: dhcp-client) and leaving only the init.d script and systemd unit in dhcpcd5.
This way, those who only need the binaries as a backend for /etc/network/interfaces (ifupdown) can install dhcpcd-base, while those who also need the daemonized automation can install dhcpcd5. Martin-Éric