(1) There are wine tastings on the CS, EB, and Auto Train.
(2) The Auto Train's commissary situation is complicated, to put it mildly, because unlike every other LD train they can't pool resources at a commissary on either end of their route. Every other LD train shares at least one end with another train (or several, in most cases...LAX, NYP, NOL, and CHI have multiple trains sharing their commissaries, both LD and in most cases SD).
(3) I ran the numbers a few years ago, comparing SCL's fares in the last five years pre-Amtrak with then-current fares to/from Orlando. Basically, sleeper fares hover about the same as the equivalent accommodations (i.e. a Bedroom is about the same as a "Deluxe Bedroom" was then), with high bucket being a bit higher and low bucket being lower On the coach side, fares are down by something like 50% on average vs. what they were in that era. Put another way, the taxpayers are arguably subsidizing low coach fares while sleeper passengers are pulling their own weight, with the sleepers' inability to turn things around largely down to a lack of equipment (I suspect very strongly that the Vacationer was a LOT longer than the Meteor or Star are today). The SunRail work isn't helping things at all, but it is far, far from the only issue slowing these trains down.
Edit: Just to explain, it seems likely that Amtrak could fill 6-8 sleepers per day on the Silvers to Florida in peak seasons. Honestly, there are probably peak-of-the-peak days where it would be closer to 10-12 (this wouldn't be daily, obviously, but at Christmas/Thanksgiving/peak school holidays?); even with slightly lower PPR, the sheer volume would do wonders. From what I can tell, the Silvers were definitely able to support this until a few sleepers were pulled away when the Heritage sleepers were retired.
In that vein, it isn't improbable that an "Orange Blossom Special" style train (maybe a second Auto Train that didn't absolutely require a car, but offered a connection of some kind to/from WAS and ORL) could generate a lot of business as well. The Auto Train is basically at capacity, the Meteor tends not to be far behind...it's a far, far cry from where we were in another time.