has anyone wondered why we have never seen rachels dad's ?

Ryan Murphy said that the two men in the picture we first saw of her dads aren't actors and he's weary of having her dads appear on the show because they won't be those men we've already seen and he's worried about the reaction.

Because they haven't been cast yet. The picture you saw in the Pilot was photoshopped.

I've heard that they will make an appearance in this season along with Artie's mom. It may not be accurate because it was also the source that told me that Sam was going to be Kurt's boyfriend T^T

Soon, hopefully. I heard they'll appear later in the season.