You still can't compare them on equal terms. One is privately financed, the other has the backing of a corporation, which however small it may seem compared to Mercedes or Ferrari, is still a stronger foundation than relying on millionaire money.
And you don't have to focus on what they said at the beginning about their involvement; clearly they're not making an effort anymore to distance themselves from the original Lotus F1, and with good reason. An established, proven successful brand is more marketable; it's way different when you're starting an unknown team with absolutely no history.
This is not about USF1 or Campos doing things wrong (they may be, but their owners have experience in the way things work in F1, so it's unlikely). Simply put, in this day and age it's hard enough for a brand like Renault to get sponsors the way the economy is, even more so for a new team without initial backing.