I can see them doing it for two reasons I think it will happen 1. Revenue and 2. The punters want it. To deny the punter what he wants is daft. the club listened on the beer thing and well, I think they are glad they did. Listening and responding to the punter is what its all about in all industries. Football no different.
Introducing beer is one thing, not the huge cost it would be to rip out seating and then have to install safe standing, would cost the club 10's of thousands if not 100's of thousands of pounds, which on top of ffp is a pretty stupid idea.