If I was expensing everything, what I might do is get one of those tins with an assortment of luxury cookies and spread them around a tier, then get some bagels (a variety of different kinds: some plain, some rye, some cinnamon, etc.) and make them into bagel chips. (Cut them into
slices, toast until crispy.)
The actors who are sweet-adverse can cherry-pick the bagel chips out of the cookies, the audience won't be able to tell the difference, and all will be well in the world--assuming your actors don't mind eating crunchy, crispy food on stage.
I also strongly recommend
cranberry relish as a sandwich topping. Even with the sugar, it's not particularly sweet: very tart, very tangy, very citrus, but that's all. You can spread it on bread like marmalades, and I've been able to freeze and defrost it without any trouble. (Although I use a different recipe.) It's also a little crumbly, though, and a pickier actor might object to that.
Speaking of marmalades, they'll add some colour to your sandwich tray without being too sweet. I'd also be tempted to try Cheez Wiz, but I wouldn't be surprised if actors objected to the junkiness.