Glossy and matte finishes are applied to pouches for different reasons. Both are designed to attract customers differently.
For example, gloss finishing helps in making pouches surface shin or glow. Such is needed to help make graphics and all imprints visible for customer attraction.
Secondly, matte is a surface finishing style that makes packages surface look dull, rough and natural. But, it is also geared towards making the surface ultra-professional for quality imprints.