They made the wrong choice, IMO.
They are going to haemorrhage users because of this. Players go where the games are. They're not going to stick around.
I get that they're between a rock and a hard place, the problem is I don't think they quite understand that yet. Or, at least, they're hoping (uselessly) to avoid it.
Without payment processors, they can't charge customers or pay devs. This is true. But without customers there's nothing to pay with.
And they will lose customers over this. And lose word-of-mouth goodwill. This is going to hurt them.
People will just move to whatever the next big thing is. Eventually the payment processors will get jumpy when things get too popular but it takes time to get up to critical mass.