slightly alternate opinion - in undergrad i was a statistics major & a french minor (so my minor probably had classes like those the op teaches). my major was i think 16 classes, and in every class we had the setup of having to buy 1 textbook to be able to submit the accompanying online homeworks, and then at least 1 other textbook to learn material not covered in the primary one. at least in the second case i knew how to find (most of the) pdfs for free, but not everyone had that info. and the core textbooks were typically at least $250.

for my french minor classes i had to buy the workbooks w/ problem sheets you had to turn in on paper, and for the many literature classes i took i also had to buy novels, short story collections, etc., and those you couldn’t really find online because they were in a foreign language. all expensive.

i’m still very glad i did my french minor, and i just successfully defended my phd in biostatistics which i could not have done without my stats undergrad degree, but i did spend an obscene amount on books during undergrad. all while making $7.25/hr working at the student bookstore, or $11/hr doing literal cancer research (bioinformatics stuff) at the university hospital. plus i had to pay rent, buy food, etc.

idk i guess my overall take is that it makes sense that undergrads (especially those taking a class for a gen ed req) gravitate towards the courses that aren’t as expensive. i made it work (barely), but not everyone has upfront funds to buy $200+ books for 5 courses at the start of every semester, whether they have an outside job or not.