Practice?? I don't need no stinkin' Practice!
Seriously, I have an entire room dedicated to my computers and musical gear. My wife works all day and I work at night, of course, so I don't bother anybody when I crank something up.
I haven't practiced per se in years, but I do learn new songs, so I guess you could call that practice. On slow nights at work I experiment with new styles and licks. Sometimes I play songs in keys that are more difficult than those I generally use, just to get comfortable in those keys in case I ever HAVE to use them. I also will experiment with different styles than I would normally use for a particular song.
Most of the time though, I could sleepwalk through the night, as far as playing the songs. I try not to let the audience see this though. They think that what I do is HARD!
With headphones, all you really need is room to set up the keyboard somewhere.
DonM