It's very interesting. I thought about this idea yesterday and I'm looking at this today. Very nice.
I'm not sure if it's ethically/legally right to scrap others' data and sell it via an API. What happens if ikea or linkedin sues them?
I know that in their requests they send some data where it's possible to block those requests and not service them. So website operators are able to prevent Import.io from using their data.
This makes sense. I think they scrap the websites with a special user agent so any website can block easily.
There's a similar service, Kimono Labs - I've used Kimono and I can say it's fantastic, powerful. I used it to scrape content from Wikipedia. It's great these services exist.
Not sure about the fine details and laws surrounding this but it's a great idea and something I'm certainly going to use in the future. nice find!