Having not played this yet, let's do some theorizing: Who wants this card? Our first guess might be low Will Survivors and Rogues, such as Finn, Skids, Preston, or Calvin. While this may help them pass a Will test (especially so on Easy where the chaos bag is more mild), +2 Will doesn't raise their Will high enough that this will really change a failure to a reliable success. In short, you can use a supply from the card and still be highly likely to fail.
I think the characters who most benefit from the Will boost are characters who have 3 (or more) Will already. This effectively adds a Guts to a Will skill check. A lot of Will tests are against a threshold of 3, which means that if you have a Will of 3 already, Tennessee Sour Mash puts you 2 over the threshold to begin with, which is usually a safe test on Standard. If your Will is higher than 3, then you are even more safe to test with this card.
Once your supplies are gone, you may want to use this for the Fight bonus and maybe take out a small fry enemy. This is honestly the least beneficial part of this card, but at least it allows you to gain some value after this thing is empty (cough, cough, Mystic spell assets, cough, cough).
A lot of characters can take this card, but I think a few people actually like it. Let's review some interesting candidates. But first I want to add that we can eliminate all the people who get their out of class slots wrecked by dual class card rules, i.e., Zoey, Rex, and Jim:
-Agnes can test at 7 Will with this card. You might think, "why do I care about Agnes passing Will tests on treacheries? She's 2 up on tests against a 3 naturally." Don't underestimate this! Agnes regularly stacks horror on herself to activate her passive, deal with her Weakness, or (and this is the big one) use Arcane Research. Being able to all but guaranteed pass a Rotting Remains or similar test on a treachery is important. Plus, since she can deal 1 damage with her horror ability, the Fight on the bottle can help her take down a 2 health enemy in 1 test.
-Leo can test 6 on Will tests with this and refill it with Venturer. This combo makes him very hardy against treacheries and can help protect his low sanity pool.
-Yorick can ALSO use Venturer on this card, but not just that - he can put it back into play after using defeating an enemy. Which means, he can recur this card using its own Fight action.
-Finally, Rita can, just like Agnes, use the 1 damage from the bottle Fight action to take out a 2 health enemy if she combines it with an evasion. Rita also has a 5 sanity pool, so passing treacheries is big for her.
Those are my initial picks for this card: Agnes, Leo, Yorick, Rita. It will be interesting to see who the community ends up deciding actually uses this card once it is finally released.