A lot of people (me included) aren't going to take the little amps seriously until they come in rackmount config.
For the huge savings these things represent in manufacturing costs over conventional heavyweights, it's the freakin' LEAST they can do for the buyer. Wouldn't kill them to put it in a 1U or 2U case.
The cigar-box configuration just screams, "this is just a secondary rig...my real rig with the effects and stuff is at home...this gig wasn't worth bringing my pro stuff to."
Or...
As many have mentioned before, for them racking a tiny amp defeats the purpose of having a tiny amp. I carry mine in a small bag along with tools, strings, cables, tuner, etc. and I can still sling it over my shoulder along with a bass in a gigbag... I know, that's not "pro" either.
Most people I know who gig professionally with their cigar boxes use them as mains, not spares. In fact carrying two spares can still be easier than carrying one rack. And they sound just as "pro" as anyone.

