Water wet, sky blue, any time a company offers any kind of voucher or alternative payment method than cash or cash equivalent (aka credit or debit) there is a rub. Said rub is usually your money gets to sit in their bank account, probably to be added to when the multiple they pick is less than a single common item, and better yet have a not insignificant percentage expire because whatever reason they don't get spent in the timeframe to gain pure sweet profit.
Nintendo have long revealed themselves to have taken a rather harsh anti consumer turn.