When you say leak, to you mean that the water gets past the seal and then drains out the drains? Or, do you mean that it leaks onto your headliner?
They are correct--it's normal for a moonroof to seep water into the drains, even when brand new. That is what the drains are there for--to evacuate water that seeps past the air seal.
Mk3 |╠╬╝|SGM|203a|Moonroof|17" Paint/Mach Whls|K&N 57S-4000 -snorkel|FFE RMM|Steeda STB, RSB|JBR bushings
Mk1|╠╬╝|Pitch Blk|Prem pkg|Moonroof|SVT Snorkel|SVT Susp|Steeda STS|Z-Eng RMM|Magnaflow exh