Half-assed hugs.
Seriously.
I hug people really tightly and if you're not gonna do it properly and just gonna sort of christian sideway hug me and pat my back and fuck off then you might as well just not hug me. 'Cause then I feel like I'm coercing you into a hug and invading your personal space or something.
I've already mentioned that in this thread.

But yeh, I hate bro-hugs and fist bumps and overall the whole fear of being physically affectionate, especially among guys.