I greatly dislike when someone chirps up, "It never hurts to ask."
Yes, it can. I can disprove it with a single question: "Any chance your daughter does anal on a first date?" From there, it's a matter of taking steps backward in intensity to realize that any "ask" has the potential to do harm. "Hey, waitress, you took 10 minutes to bring us our drinks. How about this round and the next one are free?" - The waitress now knows she's dealing with an asshole. She knows you're eking a favor from her while planning to forgo a tip on two rounds of drinks. The dynamic is damaged. She's going to Tyler Durden your food.