Taking VC put them on a collision course with Amazon because of growth requirements, and the limited ways to build the type of business that requires. Advertising and affiliate fees almost certainly don't create a large enough opportunity (interested if you have counterexamples!), and put them on that crash course with Amazon. As the obvious route to the size of business that merits VC is to attempt to cannibalize AAmazon's business. Probably by being the recommendation engine that starts sales, then starting to sell books themselves instead of being leadgen.

Had they instead chosen not to take VC: they had 35 headcount at the time of acquisition. That load probably requires $7m to $10m/year of revenue, particularly when they have to start doing data deals for all that book data / cover photos. I suspect they couldn't make the business work w/o VC given they ran two years on that $750k angel round. And even if they could, having a near-monopsony relationship with their affiliate fees partner makes them not a real business because they are highly vulnerable to Amazon predation. The same as Mozilla -- when there's just one buyer, that buyer names the price.

edit: put more succinctly: a business that either ran and grew on earned dollars (ie no vc), or a VC-backed business that didn't rely on the company you were attempting to cannibalize to play nice with you.