Just because the device says it's a keyboard without "looking" like one, doesn't mean it's suspect. Lots of input devices chose to use the human interface device (HID) USB class, since it's often simpler and has the (huge) benefit of not requiring custom drivers.

A barcode scanner, for instance, can be designed so that it just sends the digits contained in the code when you scan, and thus magically work in applications that just have regular text entry boxes in their UI.

The Yubikey (http://www.yubico.com/products/yubikey/) is another example, where a security-conscious company have chosen the keyboard HID method of delivering encryption keys to host computers.