Most festivals I'm familiar cost over $50 in an "all you can drink" format so most festival attendees go through 8-12 four ounce pours in order to get their money's worth. This all adds up to 3-5 standard 5% abv servings. Of course, most beers pouring at beer festivals are way over 5% abv so most the typical festival attendee is consuming over four standard servings of alcohol.
Yes, there is considerable debate about what actually constitutes "moderate drinking" but it's highly doubtful any reasonable definition of "moderate drinking" would describe most people at a beer festival. As far as personal health goes, a beer festival may not be any worse for you than going to a barbecue festival or even eating a big bowl of ice cream. It's just that drinking that much beer at any one time is simply not good for you.
Suffice to say that after drinking this much alcohol in the course of the afternoon, one could not legally drive an automobile for at least a couple hours afterwards. While most beer festivals encourage people to use designated drivers, taxis and public transportation and many attendees do, one suspects a significant fraction leave the festival driving in their cars over the legal blood alcohol limit. Like it or not, beer festivals raise public health concerns.
A lesser point is that beer festivals are becoming irrelevant with the growth of craft beer. There was a time it was hard to find craft beer and if you were lucky, it was one or two choices at a bar somewhere. Festivals were often the only way craft beer drinkers could discover new breweries and craft breweries could get badly needed exposure. Now, with many breweries having tap rooms and plenty of beer-centric bars with tap lists easily exceeding twenty selections, it's a lot easier to discover and explore craft breweries at a fraction of the alcohol and expense of a beer festival.
As you can probably guess, I'm going to a less beer festivals these days than I used to. That said, beer festivals still have their place and I still enjoy the ones I go to once or twice a year. It's just that when the loud cheering starts whenever the taster glasses start crashing to the floor, that's my signal to leave.