While you're skating around the internet, why don't you find some evidence that the Navy has actually used towed targets for missile tests in the last couple decades. I do know the Navy uses towed banners for strafing practice, but I think you'll be hard pressed to find any missile test using a towed target instead of a drone. Just because something exists, does not mean it is in use. I can give you a list several pages long of equipment the military still inventories, but doesn't use.
Maybe you should break out your skates and do a little investigation. It's not hard. Just one Dogpile search brings up STI who state:
Since 1990, Spectrum Technologies has provided a wide range of towed aerial target products to customers world-wide. Today, STI is the only U.S. owned and operated manufacturer of towed aerial targets. Our targets have successfully simulated threats for weapons systems such as the Phalanx CIWS, Goalkeeper CIWS, the Mark 45 gun, and Mark 75 gun, the Standard missile, and the Sea Sparrow missile. CLICK HERE to read the whole mission statement.
Now unless Standard missiles are not US Navy assets, it appears that the US Navy employs civilian contracters to augment its own capabilities. Also, heres a nice little shot of a STI Lear 35 tow in action.