I think it has to do with clout more than anything else; at adult hospitals the medicine:surgeon ratio is lower than at a pediatric hospital, and it is just easier to deal with the stupidity than have the political battle or complain. They have less administration time to put up with the battles it would take to argue about inappropriate(ly timed) consults. I imagine at programs with a strong surgical representation this is less common (i.e. CHoP, TCH, UCin, Boston). Still, I agree the griping and yelling that should be directed at the other services, yet finds its way to us, is very disappointing.
I always tried to "educate" the pediatricians about the timing/etiquette of their consults (
read: don't call and tell me "you need to do a fundoplication on this kiddo"). We also require a peds PGY-2 to rotate on our service so s/he can feel the pain in hopes it changes the way s/he consults us. It is amazing how it doesn't seem to accomplish that goal, though...