My university does the that a bit too much - last semester(and partially in this one) i had more subjects relating to civil engineering(parts of civ eng that have NO relation to my course(Surveying) to clarify) than to Surveying...
I've met few different kinds of profs(that teach subjects not related to the course)
-One wants you to get interested in the subject, despite it being mildly related to your major, balancing on the tight line between being too lax and too strict.(my Mechanics prof and 90% of field related ones)
-Another one is really strict and thinks that it is the most important subject ever(despite it being a really niche one), and forces you to do shitload of stuff(that doesn't even teach anything - its just repetitive and tiring) 5% of field related ones, 25% of non-related ones
-Yet another one is too lax about everything and doesn't care at all. 5% of field related ones, 25% of non related
- and the last kind sees no difference between someone majoring in the field and someone unrelated to it, assumes(or doesn't even care) that you have all information required(which obviously is only in the specific course) and just gives you the same workload. 49% of non-related
Most ppl teaching the surveying-related stuff assume that you are interested in it, don't give that much workload and try to make the subject interesting.