I just completed a wallfish for $75 and I couldn't help but feel for you dawgs out there who get paid much less.
I would do all that I could not to do a wallfish, even if I had to claim that I was not capable of doing one myself. Then if I did have to do one, I might not pay attention to details, such as where the rafters are and such.
If companies want to offer custom work, then they need to pay. Heck, if a customer wanted to have a new house prewired they pay $50-$75 per cable down here, so $75 post construction is too cheap in comparison.