The gloss ones have a stiffer cabinet structure plus the laquer itself has dampening properties which otherwise would be difficult to achieve and no doubt, very expensive.
Black ash and any un-laquered real wood veneers actually accelerate cabinet vibration over a small part of the band, the result being high frequency smearing unless the cabinet is reverse veneered with a silicon/silver polymer glue for Audio applications, itself expensive and derived from NASA experiments (aborted because the ceramic shuttle plating kept falling off when rolling out of hangars due to large temperature variations) The process is not used by many manufacturers.
... actually, I can't think of any at the moment.
All well documented of course.
regards