I think I figured it out. I am a general arcade guy first, and a Mame guy second. Mainstream arcade collectors tend to have 3+ machines, so the word "cab" when used is always qualified with another word, such as "jamma cab", "Burgertime cab", "Crappy Mappy cab", "old Pole Position cab", "Williams cab" etc.
Around HERE people just use the word all by itself, because MOST of the people here only have one machine.