In my pre-game meeting...
"balls and strikes are non-netotiable (sp?). If I call it a ball it's a ball, if I call it a strike, it's a strike. The pitcher, hitter or one of you 2 (one from each side atttending the plate meeting) may ask me where its at, my answer will be the end of the discussion."
This has worked very well for me.
However, threatening "Mr. Beer League all-star" to eject him if he doesn't start running to the orange bag seems to have no effect.