The average person watches television 5 hours a day. Whether you use the glasses or not, it messes with your brain's ability to interpet what the eyes are seeing. This is easily confirmed by looking at virtually any study on the effects of the effect. You pointed out yourself they warn you. But the glasses are only one factor in it. It's the 3D
itself which is a problem. The constant going from 3D viewing to reality is hard to adjust to and what causes people to avoid it.
That's all beside the point, the point was that the technology itself just isn't there for the mainstream audience yet (if ever). So blaming the mainstream audience, the people who will be targeted at and vital to its success, needs to be able to use it without all kinds of special provisions and limitations and that's the speed bump to the continuance of current 3D tech. Winking and shrugging it off won't make the mainstream audience accept it.
So while you might be able to sit and watch 3D effects for five hours and not suffer but the majority of people will and that will keep this from succeeding.
3D in theaters is a little different. First, it's in a totally dark room with no other lights or visual distractions (except for the jackasses with the phones they keep playing with). Watching on average 1.5-2 hours and not enough time to affect most people.
Add to this that the theaters paid a lot of money for these machines they were promised would bring in huge audiences (and in some cases coerced into buying), they are naturally promoting them hard to recoup their losses so you'll see a lot of screenings in 3D. How many of them are filled on an average showing compared to a showing on normal film? After the first weekend I imagine 3D showings plummet in comparison to those who watch it traditionally.
That it is not the success it was predicted to be means it will go away but it is not going to as quickly as past 3D attempts did either.
It will be a different case altogether when we get "true" 3D in the form of holographic film but that isn't in the immediate future. That will not require the eyes to refocus and adjust quite so much but it isn't a well enough tested technology to say it will be easy on the brain adjusting.
If you like 3D, that's great. Watch all you like but don't be surprised to find out if this is later called the last major year of 3D (2013D) where 3D is widely seen and that it dwindles in 2014.
That's long enough.
Though I would have loved to see any of the
Predator movies in 3D.