As an aside, I believe my first post and this one could sound like I'm trying to be a dick, I'm honestly not. I am wondering and interested. Business majors and related (like your accounting professor father) always seemed to me to be more practical degrees and not really research fields.
Yes, a lot of b-school research crosses fields. I've worked with b-school profs doing work across sociology, economics, law (to a lesser degree), computer science, and mathematics. The difference between research in those fields and b-school research seems to be that the b-school profs had more of an applied bent. The b-school research was more motivated by practical business problems.
Of course, much like programs within a discipline can be radically different from university to university, I imagine there's also a range of research styles across b-schools.
I'm not familiar with accounting research but my impression is that there's quite a lot of overlap with some areas of microeconomics. After all, accounting is either about modelling and prediction or about accurate reporting and analysis if it's not to be book keeping.
Sometimes the cross-disciplinary/applied thing just means that garbage is published by people who aren't familiar with research in another field that covered the same ground decades before. The worst though is when something is researched, disproved and they keep on teaching it in these professional schools for reasons of ideology or politics. Stuff like Howard Gardner's multiple intelligences is still taught in Ed schools and researchers like Linda Gottfredson have to deal with witch hunts because they do work worthy of a real psychology department while in an Ed school. The perils of doing work on on intelligence in a political faculty.