I wonder if the Stones would come out with a box set called "Sucking in your 70's" They of course don't really suck, despite setting themselves up for that critical one liner when "Sucking in the Seventies" came out way back when. I think the projected Blues album they're doing will be good. They don't need to do a new record.
If you listen to the wide range of bootlegs available on Youtube, the Stones were pretty prolific despite all the narcotics being consumed in the Seventies. Like in the Sixities, they mined contemporary R and B, but added reggae and country to the mix. I guess the reason the Stones have never gone the anthology route is that the illusion of a working band helps ticket sales. They were the first to recognize that if Allen Klien was going to keep the money from the records, they should just tour. The bootleggers are doing us a service by getting this stuff out there and in the digital age, no one gets paid so the fan isn't shelling out $50 for a low quality disc. A win win.