Why don't more lights have metal clicky caps?

[AaronG]

Hard clicky caps are popular on pen lights but not on AA lights or larger. Is it a feel thing or do they not work well in larger sizes? I couldn't imagine it being a cost issue as any flashlight over $50 or so the cost would be negligable. Anyone tried it and gone back to rubber boots because it didn't work well? I believe the Jetbeam element comes both ways so it is done.