Both of my clubs (approx 6,000 members and 2,000 members respectively) did or do sight in days and I'd like to think that both clubs are incredibly safe in their general protocols. My larger club stopped a couple years ago and I'm not sure exactly why but I've helped in the past and it's always an adventure. One thing about both clubs is they do/did a 1:1 ratio so there's always an experienced shooter with every sight in person. While not a perfect system, and totally reliant on a strong turn out of volunteers to keep it from going slowly, it's made sure that everyone who comes gets any help they need to improve in some way and to be fair a very small group of people resent being helped and leave as others have said. At both clubs, the firearm and ammo is checked for matching because it's amazing how many mis-matched combos show up. I'd like to believe that most of the people who've shown up leave safer and more competent shooters in some capacity.
My larger club is where I run the 600yd program and since the time that they stopped sight in days I've seen an increase of "can I sight in my hunting rifle at 600yds". To be fair most of the people who show have a gun and are capable of shoot a roughly MOA group. I'm not a hunter so I can't weigh in on people who want to know their gun can take a shot if the opportunity arrises but I think Eric Cortina has done a good job of that with his
Ethical Hunter Challenge series of videos with quite a few not so surprising results.