Scraping emails for article syndication?

Scraping e-mails is against the CAN-SPAM act. I would recommend building a list by having users opt-in to your mailing list.

But an opt-in list is for customers...This list is only targeting web site owners.

"Scraping" emails, in the sense of adding them to a list without their opting in, is very much frowned upon, yes.

Apart from the word "scrape", what you describe is one of the everyday aspects of article marketing - approaching people with websites in your niche, offering them content.

One needs to do so with a very carefully written, individual email, of course, which is mostly about them, and their site, and their content, and their visitors, and their aspirations, and their interest in the niche, and so on and so forth.

Article marketing is a relationship-building business. By forming such relationships, one gets one's content widely re-published in front of the targeted traffic one wishes to attract.

I certainly wouldn't do that part.

You shouldn't (a) put them on a list, or (b) send them anything other than an individual email, or (c) do anything that might lead them to suspect that they were receiving anything "automated" at all. That would hardly be an approach calculated to get many favourable responses. (And would often not even get as far as their inboxes, anyway).