I think Lucas is where he is because Kate is placed near Stefano. I guess because he is her most recent ex husband? Or spoilers? I don't know. But that kind of makes sense to me.
Way more sense than Adrienne sitting next to Victor. I get they are in-laws but Victor doesn't exactly like her. It'd be better, in my opinion, if they switched out Roman and Kayla and had Adrienne kind of between Steve and Victor. Or you know, Justin was present, either/or.
Actually, maybe Victor should have been between Caroline and Maggie? I don't know. The relationships on this show are too hard.
edited to write out text-speak phrase - JS