So many bad assumptions in this thread. First off is that Sonos is a big fish in a tiny market - I saw that Sonos' revenue in 2014 was 585Million and had doubled the previous year. They've actually picked up more steam in the mean time.
No real competition - I own a Play5, couple Connects, couple Amps, a PlayBar and a Sub, yet my 2 channel rig is fed by a BlueSound Node as it blows away the Connect in audio quality and handles hiRes audio. Sonos has really stepped up their game with the PlayBar and new Play5, but so has BlueSound with their Gen2 Nodes. Of course BlueSound carries an even bigger price tag, but they are making some headway with the more audio oriented crowd.
Airplay - If you are happy with your Airplay setup, great! But it doesn't compare in any way to Sonos.
Sound quality vs cheaper Bluetooth speakers - not even close. Sons has very good designs on their speakers and a great deal of innovative tech behind them. I know the BlueSound Pulse was a huge step up from the original Play5, but from what I have heard, the new device has closed that gap a bit. The PlayBar, especially when matched with the Sub is crazy good. I eliminated my $1500 Anthem AVR in favor of a PlayBar, Sub and an AMP driving my surrounds and it is brilliant.
All that's not saying they don't have room to improve. They really need to implement 96/24 HiRes to keep the higher end audio guys interested. They also really need to update the Connect and Amp devices as they have not been updated in almost a decade other than a name change. The new BlueSound Nodes have added a headphone amp, both analog and digital inputs, aptX bluetooth, 192/32 support, and higher power on their PowerNodes. I also love that Bluesound's new devices are a standard half width audio shelf width. The form factor for Sonos gear (and BlueSound Gen1) is really stupid.
Someone said they need to establish themselves as a "premium" brand like Bose....LOL thats a funny one right there!!!