AFAICS, hdparm is only installed via the laptop task, which pulls in acpi-support, which depends on hdparm. But there is need for hdparm on many other systems. For example, I installed onto a Qnap TS-109 NAS, and didn't get hdparm. I initially installed to a USB drive, as my SATA drive hadn't arrived yet, but AFAICS I would not have gotten hdparm with SATA either. Of course, hdparm has many uses on such a NAS, including configuring the drive to spin down when not in use.
[Joey Hess] OK. Do you propose to install it on all systems, or only some? If some, how do you propose to detect which system need it? Happy hacking,