Pizzagirl, I’m not sure this thread is the appropriate place to discuss (again) the pros and cons of international students attending American public universities. Personally, I think the university has done a fine job strengthening the aforementioned majors, while dealing with the difficult funding landscape in our state.
As for your question concerning what benefit UIUC is to you as an Illinois taxpayer, I would say, without going into detail, that it is similar to the benefits for a childless, older individual paying taxes for public education in general.