Coop was hesitant to leave Belle on her own, somehow worried she might vanish into thin air while he was away from her side. Reasonably, however, if they wanted to separate them, they would have done it already...
"Sure you'll be alright on your own?" he asked, already knowing the answer. He kissed her once again, soft but intimate. "Five is a long time to wait. If I miss you, I might have to come looking early."
Intimacy came easily to Coop. He loved his wife, and he wanted her to know it -- and he didn't care who overheard. Besides, it made him feel better too, thinking of her being at this diner, waiting for him.