Scottie - I was Cityflyer @ LGW, and must admit that when we were "integrated" at BA found the PA thing totally OTT. Mainly though one had to thank the CC otherwise something nasty may have happened to the tea and coffee that the pilots had asked for....
You're right though, having sat in the back a few times I do think that the FD are over ingratiating towards the CC at BA. There's saying "thanks folks !", and there's saying "thanks
folks !"