Many of the flowers are standard pink, and very common. Those roots will often be grafted to a more interesting flower.

^ yep. It's rare for certain colors to develop. Even if you try to "breed" these exotic colors, almost all of the seedlings will be pink. So the best way to share those unique colors is to graft them onto the bases if a common pink. Anything above the graft will produce the rare colors. So everyone can share and enjoy those colorations.

Aaahh...Makes sense now. Thank you jedobaTX9b and Candice (Houston).