You are safest getting it from a hotel person - that being said the sub you get at your hotel also stands a good chance of being beach schwag (i.e. sub-par).
On a couple of occasions I have asked the restauranteur where I'm dining if they had any thing above beach schwag I might enjoy for dessert.
On one particular occasion I wound up knee walking backing home thanks to this ploy, but it wasn't beach schwag.
It's a fair question and you'll probably get better answers than mine.
I guess the main thing safety-wise, is develop some level of trust with one of your hotel employees and ask them to get you a bag of subs.
If you don't eat subs often it may even meet your standards.
I get a lot of my subs from Colorado so I'm a bit jaded.
I've had great subs "on da rock", even better than Colorado but those have been isolated instances.
Party on!
