My band (lightly amplified acoustic folk) was playing an afternoon gig at a brewpub. A couple with a toddler came in and the child began to emit extremely loud, ear-piercing screeches at 40-second intervals.

After a few of these, I stopped in mid-song and said, not in an unfriendly way, "I can't work under these conditions. Please restrain your child from screaming."
The young couple was mortified and let soon after. My band members berated me for being rude. Was I?