There are many good answers already, but my two cents is that there are many standard statistical methods that work on basic "data" type problems. If your data is spreadsheet type data, where it has some number of basic float inputs that lead to some float result, you will probably use ordinary statistical methods like boost. NNs might be able to achieve the same results but they probably won't do much better.
In fact I remember talking to an ML guy with a PHD who was working on one of these types of problems and I asked "why not try NNs on this problem". He looked at me with disgust and said something akin to "it's provable that NNs can never do better than BOOST, so why use them?"
However, boosted decision trees don't work on image analysis at all, so these types of problems have become the standard for NNs.
It is also worth noting that people are more likely to try image problems if everyone else is trying image problems, because then it is easy to compare multiple algorithms together.