I just think, as huge music fans, we forget about the average fan that makes up the majority of music listeners. The average fan likes singles, will collect albums but not nearly as many in as many varieties as we will, and will typically have more rigid taste in what they like. If they liked Core, they likely won't like Tiny Music...Songs from the Vatican Gift Shop. One need only look at the 8 million who bought Core and the 2 million who bought Tiny Music...Songs from the Vatican Gift Shop to see this. There was no lack of promotion or awareness of the 1996 album, and while I admit the tour was flubbed, it was just too different from their established sound for the average fan. Make no mistake that unless you're U2, and even they're not infallible anymore, it is the average music fans that cause an album to sell multiple millions. STP's sales have only dwindled further as they have gone further away from the sound of Core. Each album has sold less. Purple lost a quarter of its predecessor's sales, Tiny Music...Songs from the Vatican Gift Shop lost two-thirds of its predecessor, No. 4 lost half, Shangri-la Dee Da lost half of that, and Stone Temple Pilots has lost around three-quarters of that. That's what happens when you release albums that fly in the face of what your average fans want to hear--another "Plush", another "Dead & Bloated", another "Interstate Love Song", another "Big Empty".
Alice in Chains' basic sound is instantly recognizable, from "It Ain't Like That" to "Check My Brain". Yes, they are more versatile than the average hard rock band. But no one is going to mistake "Got Me Wrong", "No Excuses", "I Stay Away", or "Rotten Apple" for anybody else. Despite being different, it is quintessential Alice. This is not only due to their style, but to Layne's instantly recognizable voice, as well as the 4th interval harmonies that not only weave in and out of Black Gives Way to Blue, but also Jerry's solo albums and Mad Season's Mad Season. Alice's record sales reflect this. Facelift went double platinum, Sap went gold, Dirt went quadruple platinum, Jar of Flies went double platinum, Alice in Chains went double platinum, Unplugged went platinum, and in a year Black Gives Way to Blue has gone gold. They have a consistent sound, and consistent sales. I'd further argue that Sap is the least Alice sounding of the discography, and it sold the least, Unplugged is a live album so it shouldn't count, and that it's tough to judge Black Gives Way to Blue just yet because it is a new singer and a year old. If you take those out, a band that is instantly recognizable has gone double platinum, quadruple platinum, and double platinum.
Not only is STP's music more versatile than AIC's, but Weiland's chameleon-like ability to change his voice makes it more difficult to know that it is him singing, and therefore (likely) STP. Sorry, but saying that "Man in the Box" to "I Stay Away" is the same as "Dead & Bloated" to "And So I Know" is just insane.