The flipside: If you need a business loan would you go plugging your details into a random website? What quality of client would you be getting if you bought those leads?
I have never done a serious search for a business loan here in the U.S. However, I was recently looking into a mortgage refi for my daughter. There were quite a few "big name" sites (e.g., nerdwallet) that offered the best rates through their partners, which were all established banks. It allowed you to apply online and then, theoretically, your application would go to the partner you chose. I did not fill out the form there and instead went directly to the bank's website to research further. However, had I filled out the form with the aggregating site, I suspect that I would have become a "lead" for them to provide to all of their partners and possibly sell to others. If that had happened, I would have been an "annoyed" lead and not a "hot" lead because I likely would have been overwhelmed with sales pitches from eager loan salespeople. My point is that any site you might buy these leads from will likely sell the same leads to many, many other buyers and they will be overwhelmed with pitches, offers, etc. Not the high quality lead I would be wanting to spend time on.