[That is exactly why he's saying absolutely nothing about said things. The less you know about that, the better - you don't need anything else to stress you out, now.
Which is why he's relaxing just slightly when he notices his choice of cafeteria was right... but then, he's shaken out of that when Art finally orders. For a moment there, Bucky's not sure whether or not he should laugh or cry. Of course.
In the end, though, he does neither - instead, he waits until Art's order is done, and then adds, with a tone that is entirely nonchalant and casual:]
Yeah, an' I'll have a spaghetti bolognese, two sirloin steaks with fries and vegetables, a Prawn Caesar salad and... let's take one o' those plates o' grilled salmon, too. An' a bottle of wine and another o' water, too.
[And when he's done, he smiles at Art in a way that's a very clear message of "you thought you'd get away with it, didn't you".]