I think that post was in relation to baby chicks, which probably ate it thinking it was food. The same likely would have happened if they ate as much other bedding, no?
likely because the grounds are brown, so some colour would be transferred when wet. If you brew coffee with used grounds, it would make a really really weak cup of coffee, and that's when you do it with boiling water. If you're very concerned you can write to the company. I would not fret about it