There is a rather posh looking hotel near the Gnome's abode called the Milford Plaza. Tall, imposing and with besuited doormen fighting each other to carry your bags inside, it has a huge neon sign on top of the building to advertise itself.
As these lights must be at least two stories high, the expense of illuminating the whole name was presumably too prohibitive, so it is limited to 'M Hotel'. Even so, it conveys the appropriate marketing message of a modern, plush and trendy lodging space, ready and able to supply all your holiday or business needs whilst temporarily residing in the Big Apple.
Unfortunately, a couple of weeks ago the bulb in the 'H' went out, leaving this grand - and no doubt expensive - establishment advertising itself as a simple 'M-otel'