This is a problem I face. The rationale is my school has to justify its research funding based on specific academic areas (called units of assessment) as these form part of the research excellence framework assessment so we are only allowed to undertake work that can be submitted in these areas. This is not good for interdisciplinary collaborations.
It does happen. Sometimes, we tend to hear that onomastics, which is partly my field of study, is not linguistics, that it belongs more to geography / history. What you get as an outcome is a number of publications in the journals that, despite being of high quality, do not fit into your field of research. Changing this should be the key task for the people in charge, as these conditions are openly hostile to interdisciplinary research as such.