Duck foot color...e ducks

[3Kids&2Ducks]

I have 2, now full grown, Swedish Blue ducks. I have a question about foot color. One has black feet like they are supposed to....i googled and everything i read says black feet and bills. The other has yellowish feet...not black but more like a dirty yellow, even though they are clean of mud and dirt.

Is this normal? This particular one had black feet with some light patches on them as a duckling.

 

[3Kids&2Ducks]

*bump*

 

[Big Dreamer]

It may be pet quality. Not to breed standards. By all means still a blue swedish..just a lower quality one.