I suggest, if it is not wanted, to get suricata started at boot by default, then just leave the package as it is.
However, in that case, you should mention the opportunity by systemctl in the README.debian (or better let the user decide during install) if he wants it running at boot or not. I personally found the solution with systemctl, so this regardless what you decide, IMO this bugreport can be closed. To discuss this is a welcome decision and real open-source-thinking! Best Hans