I'm a postbacc student who began college back in 2007. As far as I can tell, the practice of giving mandatory homework is a fairly new one and basically a sneaky way of forcing students to give the textbook publishers hundreds of bucks per class. You can buy used textbooks or get older editions for significantly cheaper, share a book with a friend, etc., but if you need the $150 online program to do the homework that's part of your grade, you have no options.
Back when I took biology, there was no homework aside from I think we had prelab assignments to fill out in our paper lab manuals. Now bio students at my school have online homework problems.
I mostly hate the entire concept. For one, I'm broke. As an undergrad, I got away with paying like $10 for a lot of my books because I bought old editions. Can't do that anymore. Secondly, it makes college too high schoolish. One of the biggest appeals of college used to be that I could prepare for my classes at my own pace as long as I had all of the material down by the test date. Now there's much less freedom and flexibility because of constant homework due dates.
There are benefits in some classes, though. In gen chem, the test questions and homework questions were COMPLETELY different types of questions. The homework was just a blatant waste of time and money. Everyone in the class learned to just look up the homework answers on Yahoo Answers and move on with studying for the actual exam. But in my calculus and ochem 2 classes, I had teachers who would put some of what were basically the exact same types of questions on the exams. It was helpful to have an idea of what types of problems to expect going into exams. At least I felt like I got something useful to me for my money.