I asked my husband, since he's done retail pharmacy, "You ever have a patient for a consult who was on the phone? What did you do?" He said, "I told them, 'Any time you're ready to be off the phone. I'll be over here working.'"
If the meds can't be given without a consult, they can't be given out without a consult. However, it sounds like no consult was given, and for a new prescription, there should've been one--at least under CA law, where the pharmacist must consult on new prescription regardless of any doctor instructions, unless the patient waives it. My husband said doctors usually don't give instructions, may not be familiar with other meds used by the patient from other doctors (interactions), or discuss about side effects, as he did/does.
So I'd say the customer was rude. She stood there with her headphones on and talking and never made it clear that she was ready to proceed. True, the pharmacist could have told her to alert them she was ready, but the customer doesn't imply that she volunteered to do that, either. She just stayed talking and, likely, the pharmacist assumed she wasn't ready to end her conversation and listen up.