Before CDs existed LPs were mass marketed. Not Amazon style mass marketing, because that didn't exist back then. But I encountered big box LP stores long before I encountered a big box book store and I was a member of at least 3 record clubs.
Those links you provided don't mention vinyl, they're all about digital and on demand CDRs. I've bought a few on demand CDRs before and I'd buy digital if it was lossless, but I won't buy it compressed unless I have no other choice. On demand CDRs have been around for quite a few years. Arkivmusic.com's business model is based on it. Hopefully, Amazon's shop will have stuff that's never made it to CD.
The link in your OP says that LP sales were the highest since 91 when Nielsen started tracking them. The problem is that by 91, LP sales had already collapsed. They were regulated to the back corner of a store, if they carried them at all.
I can't find actual numbers but I did find one article that states that CDs out sold LPs in 88.
Digital Audio Essentials: A ... - Google Book Search This jives with my experience. I went on a 3 month vacation in the winter of 87-88. Before I left, the majority of the space in music stores were LPs and they sold a few CDs. When I came back, most of my favorite stores had converted to selling CDs in long boxes. It was an unbelievable transformation in just a couple of months and very noticeable for me because I had been out of music stores for those 3 months.