That "volunteered me" thing hits a nerve. I see it all the time with tradespeople. Family or neighbors just assume your time and skill are free for the asking. It’s not just carpet. My buddy who fixes cars gets hit up for free brake jobs. Another friend who is an electrician gets asked to wire a cousin's shed for a six-pack. They don’t see it as losing paid work, but that’s exactly what it is. Your job is your job, even if you’re good at it.
My uncle tried that with his plumbing work and it backfired. People just took the cheap family rate and still expected him to drop everything for them. It made the whole discount feel like an obligation instead of a favor.