But also in Japan the times have changed a bit and the people have quickly understood that they can make a lot of money with Christmas

Yup! They realized indeed and also hopped on black Friday recenlty. KFC is the master of it though right?

Christmas was, and still is, a secular holiday in Japan -- a country where less than 1% of the population identifies as Christian -- and in the 1970s many people didn't have established family Christmas traditions. That's where KFC came in. The company launched its "Kentucky for Christmas" marketing campaign in 1974 and the first iteration of the party buckets soon followed.

source https://edition.cnn.com/travel/article/kfc-christmas-tradition-japan/index.html