Remus did not draw attention to the fact that he thought he saw a glistening in Sirius' eyes. He didn't want to make him feel self-conscious or take away from the tender moment they'd just exchanged. He went right along with Sirius, and returned the grin as he looked at the food.
"So it would seem," he replied. "Perhaps I've made more late night visits to the kitchen for sweets than I realized." That likely wasn't true, but Remus had always made the effort to be kind to the elves and treat them as he'd want to be treated. He knew what discrimination was like for people like him, and thought that elves had it much worse.
"It looks delicious," he said. Feeling a bit less shy, he leaned in a little closer to Sirius again. "So do you." He stole a kiss, then blushed a bit and leaned back, as the shyness crept back in.