Well I guess directors and other people that make the movie want to use the best technology to enhance the movie experience and to lure more viewers to watch the movie. For Example: Avatar. (with the blue people) Jame's Cameron had the idea of Avatar for years (1994). But he never started the development of the movie Avatar until he thought that the technology needed to create Avatar to it's fullest was finally made for the movie industry. With enhanced technology Avatar was at the top charts basically and many people loved it (like me). And 3-D is just a part of that technology b/c in my opinion it's just another advantage of the 21st Century and people tend to use stuff to their advantage. Yup, lot of info I put there, don't know why I bothered.
When I pay to go to the cinema I want it to be epic; at home slobbing on my sofa I'm not bothered, but when I'm paying £10 to see a movie once it better be good. I love 3D because it seems (in my mind) to make the whole movie more accessible, and just gives depth to the illusion of cinema
1)Make a good movie, 2)Make it ten times worseby adding that eye straining, almost never noticed 3d effect, 3)Charge more for this peice of crap, 4)??? 5)Profit
The only reason so many movies re doing 3-D is because it helps sell tickets. Why? Because there are just some people out there who thik, "Oh it's 3-D! It must be good! Let's go see it!"
I have to admit, it does spice up movies with lots of effects quite a lot for some people. My mother, for an example, never wants to watch a 3D movie because she begins to feel sick. I, however, really like the depth that it gives. It's all about personal preference.