"What causes blue eggs?" & "Why did my recently butchered chickens all taste like feathers?"

Today at church while selling eggs, I was asked two questions.  

Question 1:  (From Rita) "Why do some chickens lay blue/green eggs, & others lay white or brown?"  She told me she preferred the blue/green ones over the other colors because she blows them out then paints landscapes and other images on them, like a round canvas so to speak.  I asked why she didn't use white eggs in that case, and she said the blue/green hue of the shell adds a depth to the paintings that white & brown shells don't.  She specifically prefers the blue ones I guess, but her dozen had one blue, one green, majority brown, pink & whites and she said she would be happy to work with what I had given her.  Now that I know she prefers one color over the other, I can make sure she receives more of the colors she wants. 

In the process of the conversation I explained to her that it was due to the breed, different breeds lay different colors, but that isn't what she was asking and wasn't 100% satisfied with my answer.  I also told her I would be having some Easter Egger's/Americana's/Araucanas coming on 4/21, but then realized that that isn't official for sure, because I wasn't able to nail down any yet, because I don't have an incubator yet, and am unwilling to purchase hatching eggs prior to having an incubator and making sure it works correctly.  Also unwilling to buy expensive eggs prior to testing an incubator out on less valuable eggs. 

Anyway, due to Rita's question, I have done a little bit of google research.   According to HenCam: A Chicken Keeping Life it is "metabolically costly" for hens to produce blue/green eggs, because it requires a chemical called "biliverdin" which is a derivative of the hemoglobin found in blood, and that the "Biliverdin is added to the calcium carbonate earlier in the shell-making process, and so the eggs appear blue all the way through. Chickens that lay greenish, gray, or dusky blue eggs produce both biliverdin and brown egg pigments. The brown overlays the blue."

Question 2: (From Curt) "When we butchered out our 15 (2-year old) hens last fall, all the meat tasted like FEATHERS!!  Why is that??"  I don't know the answer, so I've posted it as a question in "backyardchickens.com" so we will see what comes of it. 
4/9/14 Edit:  After asking BackyardChickens, the basic consensus is that the meat probably got tainted by a feather or two when they processed the meat, and that feeding the flock table scraps shouldn't effect the taste at all.  No one really seems to know why Curt's canned chicken meat ended up tasting like feathers, but that he should discard the meat, and try again next year.