I always assumed there was a reason that shoe trees are typically unfinished wood. Wouldn't the glossy coating on these affect the ability of the wood to wick moisture/odor from the shoes?
crafty35aThe moisture wicking effect of unfinished shoe trees is over-exaggerated. My shoes are bone dry the morning after I put in the shoe trees, with both finished and unfinished shoe trees. A few hours difference doesn't matter. If you're truly concerned about this, then the matte finish is more moisture absorbent than the glossy finish.
Many high end makers like Gaziano & Girling ($1000+ retail shoes) use finished hardwood shoe trees.
crafty35aIf wood has a wicking" effect I doubt it is significant otherwise people wouldn't make boats out of it. Realistically, evaporation is doing the work to dissipate moisture.