To be honest I like the variety. First, surname or nickname; all good.
I like variation when it represents the international quality of football. For example, nearly all footballers with Portugese names go by their nickname and it has been so for god knows how long, so when a Portugese or Brazilian player is in the team, that aspect of their culture comes along with them.
Japanese family names have historical context as well as direct meanings. Nakamura means "central village" and Miyaichi could be translated to "town by the temple." First names, however, are often trendy and meaningless in a broad sense and are not an important part of your identity in Japan, where 99% of people call you only by your family name.
It probably bothers me even more because there's this popular notion of "being international" but Japanese seem to believe that you can become "international" by giving yourself a foreign name and learning a cool language like English, Italian or German instead of opening up your mind and your perspective. It's shallow and tiring. I'm too jaded.