You are alone in this

To add a datapoint to this thread now that it's reawakened, the St Regis Bangkok referred me to their business center who handles such requests, and they offered me several quotes for shipping speed and cost. I think they added a small handling surcharge. That's the level of service I would generally expect from a top tier property.

Asking a guest to send someone to put an item in a box or envelope seems ludicrous to me -- it's a few minutes of effort for the hotel vs a huge hassle for someone to arrange remotely in an unfamiliar city, with an unfamiliar language.