Space is a valid reason. Even in a regular sized house. It's a matter of priority what one wants to do with their space.
edit: that was aimed at iamweasel2 
I am uncapable of coding on an emulator. It is much better, faster and reliable to code using tools like megaflashrom sd scc+ and eric boez SD card reader, which both have their advantadges and disadvantadges, and I used both to develope and code Life on Mars.
There's no contest, really. Emulators allow things that aren't possible on real hardware (breakpoints in ROM, checking VDP registers between each Z80 instruction executed, quickly change some memory locations or Z80 registers on-the-fly and restart execution a few steps back, etc, etc). Any of such things can help a coder a lot to figure out what's going on, and get things running as intended.
Of course not all emulators support all such features, emulation is never perfect, and there are some very good debuggers to use on real MSX. Perhaps a good debugger may even simulate such feature(s) somehow. But one way or the other, debugger is in the way so there is side effect(s). So in the end: no contest.
That said: a lot depends on what developer is used to, and how well he knows his tools. And of course that has effect on productivity or end result. So I wouldn't argue with a coder who does a better job using real MSX for most of the coding. Not to mention that all testing is done on real hardware in that case... never a bad thing. 
I am uncapable of coding on an emulator. It is much better, faster and reliable to code using tools like megaflashrom sd scc+ and eric boez SD card reader, which both have their advantadges and disadvantadges, and I used both to develope and code Life on Mars.
Me, I exclusively develop on emulators, I use the real MSX just for occasional testing. My iteration time is just so much faster, and I can use my PC development environment, with modern editors and tools etc., without having to transfer files to the MSX all the time. Also I have no risk of messing up my HD when the game crashes in some unfortunate way that the hard drive gets corrupted 
. (Has happened to me several times back when I was still developing on my MSX.)
I’m coding in assembly, but also for Basic I would probably do the same, you can load them as ASCII (or put a small Basic tokeniser tool in the build chain), fast forward, etc.
Not that there’s anything wrong with developing on the real machine of course! But I moved to PC cross-development because of the benefits. Just worth noting, on the topic of whether emulator users are "real" MSX users, among MSX developers there are also many who use emulators, if not most of them.
p.s. I find making a distinction between "real" and "non-real" MSX users quite unproductive and unnecessarily divisive. Our community is small, why is there a need to introduce some kind of hierarchy of how "true" and MSX user you are? Especially if that’s judged based on the use of emulators or not, it’s crazy to me.
