I have nothing against instructors using the name of a military unit to sell either their own hand-to-hand combat system or one that is used effectively by that unit. Not at all. For the most part, I see this as a marketing thing and each instructor/author has to make decisions on that front.
If you want to connect a USB device to an HDMI device then you must use a converter box. This is a set of electronics that change the protocols and signals. The only adaptor which works is the DVI-HDMI ones.
USB flash drives have become an easier way to store and transfer data than burning CDs and DVDs. USB flash drives are nearly infinitely re-writable, whereas most DVDs can only be written to a few times. The flash drives are also easier to carry around, without worry of scratching. In order to transfer the contents of the DVD to a USB flash drive, you can simply copy and paste between the two.