"Snub out a cigarette" for "stub out a cigarette" in AmEng

My bilingual dictionary marks "snub out” as an Americanism for “stub out” as in, “He snubbed out his cigarette.”

Is this phrasal verb common enough in present-day spoken AmEng that it can be used quite safely in general conversation?

Please consider this Ngram.

Since the primary meaning of snub is, “ignore, behave coldly toward; slight”, I would tend to think “snub out” might suggest a certain way to put out a cigarette or cigar.

I don't think I've ever heard snub out used of cigarettes, etc., but here are some counts of written instances in Google Books showing that it's certainly used (just not that often by comparison)...

snubbed out his cigarette 3,150 results
snuffed out his cigarette 7,490
stubbed out his cigarette 89,200

The problem for me is that I consider snuffed out to be a perfectly valid (if somewhat less common) usage. In my understanding, if you snuff out your cigarette, you stop it burning by pinching off the burning tip (also referred to as dogging it, in my vernacular). Alternatively, using liquid - spit, or a drop of wine transferred from a glass via your finger. But crucially, you can relight it later, and smoke the rest of the cigarette.

If stub out a cigarette, you've probably mashed it up so much there's no chance of smoking any tobacco that might have been left.

So I've no idea whether the (portmanteau? malapropism?) form snub leaves anything capable of being smoked later or not. If so, rather than being a blend of the two more common forms, it might relate to snub as in snub-nosed (short and turned up). Perhaps the allusion is to making a shorter cigarette to smoke later.

Stub it out is written on street cigarette bins, I saw it in Glasgow, Scotland. It is probably used only in UK, that's why people worldwide don't know what it means.

Source: http://www.flickriver.com/