I'll only buy floppies for a few reasons: A) it's a #1 issue with a cool cover for a character I like, or B) it's a limited series that I actually want to read. I never really buy floppies for ongoings except for in the odd case, and I'll normally opt for the trades. I refuse to read any comics/manga digitally.
As for what I see in the future of floppies: I don't really see them ever completely phasing out single issues. There's still a very steady stream of cash flow coming from single issue sales, and variants do sell quite well, for the most part. I'm not worried they'll be going anywhere.