[dheera]

I'd say the act of web scraping alone, is almost never unethical if you are careful to not cause undue load to servers. From an ethics, not legal perspective, I don't see a whole lot of difference between your computer's silicon eyes and your organic eyes just looking at something that's already in plain view.

It might be illegal in some jurisdiction; IANAL but I think you can just get out of that jurisdiction and scrape away if that is the case. It might violate some ToS but ToS isn't law; the consequences of violating a ToS are usually on the order of getting your IP banned.

What you do with the stuff you scraped can be ethical or unethical.