If the business model is "Attract lots of people and then sell ads." then the service will be oriented towards whatever provides the most clicks.
If the business model is "Get big, and then get bought out." then the service will quite possibly vanish.
For throwaway services that I can switch to a new provider for, this is possibly acceptable. But for anything I might want to base my own business on, or store information I will care about in the future, doing so would be foolhardy.