Well, Google has done so in order to get around Chinese censorship (started redirecting google.cn to google.com.hk). I would call them a legitimate business.
Also, on the topic of Google, search engines sell your posts as well! They're usually free for users, but API access is always paid. Google had a paid API, Bing has it, Kagi has it, etc. That means that currently I can pay Kagi to return a post of yours, based on a query, with a snippet (granted, not the full thing). Same goes for enterprise - always paid.
Now, from what I can see, the website doesn't inspire trust, their tactics are invasive and it either intentionally doesn't respect opt-out sometimes (& instance blocking) or has a few bugs that conveniently aren't fixed. So, I don't like the execution. I do like the idea however - index and provide alerts based on keywords. If one is made that is much less invasive, more trustworthy and respects opt-out, I would have no problem with it. Charging for API access and Enterprise is also fine since that kind of service requires infrastructure that isn't exactly cheap.
<small>In summary: Pricing model seems fair to me, and I like the idea but their execution (invasiveness, dubious respect for opt-out & trustworthiness) is bad and I think if it either fixes its flaws or a competitor is made, I would have no problem with it.</small>