Lastings Milledge and baseball culture

In Dejan Kovacevic's July 07 story about Lastings Milledge, Dejan discusses how Milledge has a reputation for rankling veterans in his previous stints.  Dejan dropped this brief anecdote:

The catch, as [Milledge] readily conceded, is that he hardly has been one to subscribe to standard baseball culture, a la Doug Mientkiewicz last summer correcting one of the Pirates' youngsters on how to set down his batting helmet.

I don't recall that incident. Anyone have a link or could give me an explanation? I'd ask on the PBC blog comments but that would require me to (1) subject myself to that cesspool, and (2) risk incurring the wrath of yinzers by implicitly questioning Dirty Doug. Maybe this explains why Doug got into a shouting match with Randy Johnson: Randy probably didn't show proper reverence to the rubber.

I'd really like to know why proper batting helmet placement technique is considered such a vital part of clubhouse chemistry and baseball culture.  I never played baseball beyond Little League--I was terrible--but I've never heard of that. Am I simply ignorant on this point?

Beyond that specific issue, how important is all this stuff? I understand the idea that rookies should know their place and be humble and all that, but this seems silly. Milledge could eat ice cream out of his batting helmet like it was a Dairy Queen sundae for all I care, so long as he hits well. 

If Milledge is blatantly disrespectful to his teammates that's one thing, but most of what I've read seems more like the batting helmet example.  In discussing the Pirates roster Milledge comments, "You're not going to have guys looking down on you because of how many years you have. Everybody's pretty much at that same level, on the same page, and I'm looking forward to it." If I were Milledge, I too would be ticked off if some mediocre veteran looks down on me and tries to assert his dominance clubhouse by telling me I had to follow his ways of doing things.