How effective is anti-static device for LP play?

Actually I'd like to tweak my question...It is really the question of how effective do some of you think a device like the Milty Zerostat could be,if humidity in music room is at a constant 50% or so?Would I really benefit from it in good conditions,with clean LP's?

Does the act of simply playing a disc add some degree of static to the disc,even in good humidity.

Does static come about due to other circumstances,and can this negatively effect music reproduction,with humidity not really being a big factor?

Thanks for the responses,in advance.-:)