According to an essay written by Roppa FURUKAWA, Kansai is the birthplace of the custom of eating grilled meat and other ingredients after dipping them in beaten eggs, and reportedly, there was no restaurant in the Kanto region that offered beaten eggs for gyu-nabe based sukiyaki dishes at the time.
古川緑波のエッセイによると、焼けた肉は具材を溶き卵に潜らせて食べるのは関西発祥で、関東の牛鍋をベースとしたすき焼き店では、溶き卵を出す店は無かったらしい。