Vanilla is a product of Lussumo:
Documentation and Support.
So, instead of editorial philosophy and curation, you'd pay a lump sum to have a publisher stick a tube down your throat.
None of the magazines suggested are doing anything as remotely cohesive as New Worlds or even Coilhouse, which is putting itself out there with a pretty damn clear set of principles. (Locust is different, it'll always be a niche publication.) At best these sites are publishing a selection of short stories that amused the slush readers and editors enough to want to publish them. But they're not editorializing or defining themselves as anything other than magazines that publish a genre.
Consider this to be your dismaying PSA of the day: Apparently, if you're a Kindle owner with a magazine subscription, and you decide to stop subscribing, the back issues you previously downloaded are also lost—for good.
Yes, that's a problem, but that's really no different to paying to get through the Times pay-wall.