It seems to be a normal practice for network device manufacturers (like HP and IOmega) to leave the password protection wide open on all sorts of network devices like printers, scanners, security camera systems, network storage devices, and so on.
I suspect this is done to make the devices easier to install and use, increasing their user friendly feel while lowering the cost to support. Sadly the side effect is that hackers can easily connect to these devices and access your saved data. So while your computer may be secure with a password, your network devices may be wide open to hacking.
To protect yourself dive back into the manuals for your home network devices and learn how to activate the security functionality. Be sure to pick a difficult password to break that contains numbers, special characters, and most importantly words not found in any dictionary.