(o_O) Most Transformers can't physically emote with their faces or heads... and not all Shockwaves have mobile ears. The main reason why the original G1 Shockwave's ears move is because they need to fold down in gun mode; so it's a necessity of design. Heck, when I was a kid I didn't even know Shackwave's ears could move up and down -- at first I kept transforming him to robot mode with the ears down. I accidentally discovered one day that they could move up!

I don't have Action Master Shockwave, but I suspect that his ears can't move. Binaltech Shockwave's ears also can't move (and that's the most complex Shockwave toy ever made!). Energon Shockwave's ears can move back, but not forward. Animated Shockwave's ears move because, like 1985 G1 Shockwave, it's part of the transformation. So really... considering that including separate parts (and thus increased costs) for mobile ears wouldn't effect the performance of the toy, I don't see the need for Hasbro to include them.

Besides, as Shockwave would say, emoting is illogical.