Before I was able to find a job, I was taking some classes at a local college. I was at the end of my financial resources (I could barely afford shoes) and they wanted me to buy this expensive textbook and problem sets online. I already had a perfectly serviceable textbook, but I wanted to be able to practice for exams. I asked the prof. if he could print out a few from his laptop or something, and he flat out refused, even when I told him that I was too poor to afford it :-(. There might have been some miscommunication, but there are times when demands are clearly unreasonable.
A kind professor can sometimes use their administrative privileges to create a "testing" account, which they can pass on to a student. Many of the courses I took in my undergrad degree required electronic components which may cost as much as the textbook.
