Hmmm, I wonder if that's it and the flower meanings/flowers equals emotion is the key here, because that fits well with the usually soft nature those particular AUs seem to have.

Not dissimilar to "the way to a man's heart is through his stomach" bakery AUs.

Made perfect sense, thanks for thinking that one out and articulating it for me. I am always interested in what catches fandom's attention, even if it's not my bag.