I've Googled some info.
Old DotA players are used to autoattack and have it on even in D2. I was and I am always running around a lot. Just an old habbit from W3 DotA to prevent autoattack.
Yet I don't have autoattack on in D2. I think there's a third option in D2, a hybrid one. I use that.
Autoattack can be prevented if you set lower aqusition range for your hero, but that have to be set in editor.