WWE could have made money on ECW for many years, catering to the niche audience that spends money on ROH, CHIKARA, DGUSA, PWG, etc.
ECW, if left alone and allowed to be what people wanted it to be, could have stayed in those small & mid sized buildings, as a third "tour", while at the same time acting as a pseudo developmental group. The AAA tour, if you will.
With Heyman developing the talent, WWE could have had their own little ROH-eqsue promotion where new talent could cut their teeth on national TV and in front of rabid crowds before hoping on the big show.
People were spending money on ECW DVD's and PPV's and the ratings on SciFi were strong well beyond the initial nostalgia period. Heyman was all set to change the direction from hardcore nostalgia to MMA inspired "serious" wrestling. It would have been different enough to satisfy the smarks into thinking it was "cool" despite being big corporate wrestling.
But Vince had to have his extremists and vixens and Bobby Lashley's and it sputtered out to the tune of a 90,000k buy PPV embarrassment at the end, because they drove off the smarks and the mainstream could not give a single fuck. I guess smark money wasnt green or something. Vince insisted that "a few thousand vocal northeast fans" was all the old ECW vision could attract, but the DVD sales, One Night Stand buyrate, and early TV ratings proved that to be false. He's just stubborn and needed to do it his way. And it failed.