Markings on rugby players socks?

Question

I have recently noticed that all the players socks are marked differently on the back, ie some have small patches of contrasting colour at the ankle, some have stripes of colour all the way up and others have assymetric flashes on them.

Is this so that players positions can be determined during rucks and scrums by other players on the ground?

My husband is very surprised that I have noticed anything this low down...

Answer 1

They certainly dont represent  "players positions during rucks and scrums"

Maybe its just a personal thing. Like shoes.

Answer 2

With some players their socks represent the club they play for.

Answer 3

As per previous answers.

Answer 4

they know which socks are theirs after being washed