Just to throw in my 2 cents.
Joe, I like your aim here, it is off beat from what everyone else is considering.
When you are buying donuts, buy donuts. Don't let the destruction of potential enemies distract you from your purpose, which is to buy donuts. That is the death mentioned in Joe's 2nd post.
Takuan Soho, to Yagyu Munenori wrote:
Whether by the strike of the enemy or your own thrust, whether by the man who strikes or the sword that strikes, whether by position or rhythm, if your mind is diverted in any way, your actions will falter, and this can mean that you will be cut down.
Now in the case of purchasing donuts, alternatively the above would suggest that you will be cut in front of in line whilst considering just how much this person's neck might actually sound like celery snapping.
If it was chado, or kyudo, or iado, we would see this immediately. You are there to perform the task of making tea, letting fly the arrow, or drawing the sword. It's an exercise in presence.
The funny part here is that, well, I'm just buying a donut, no need to focus. If what you're doing is not deserving of your full presence, then why do it?
I love donuts, and I get distracted from my purpose plenty, nor do I do nearly all the worthwhile stuff I should be doing. But then 'worthwhile' as a qualifier is another thread entirely.
As for what everyone else is discussing
, the first thing I look for in environments when I get less than perfectly comfortable is obstacles, primarily what can I situate between myself and them, such as tables, pillars, unlucky passersby (kidding...). Then I size 'em up.
"The whole of reality is in the Center of Goodness. The Center is the Void -- but all Goodness surrounds and defines the Center of Emptiness. The Void is the Fullness and the Center of all Goodness --- but without the Goodness that surrounds, the Void is empty and without Form. As the emptiness in the belly is at last filled with Goodness -- so too shall the Goodness be consumed and at last become the Void -- joining the Goodness and Void as ONE -- at the Center."
The zen of donuts and their holes. incredible ... : )