One of the problems with the 0-1 value is that you cannot make a 1:1 relation with the Sonos volume. That would result in the Sonos to play at 100% of the volume each time the Homey has restarted. Also, when you use two remotes or more (around the house), “syncing” the remotes with the Sonos volume would be a problem. In my understanding, it would be more useful if Athom would provide the “relative” value (for example +30% or -15%).
But then again, maybe I am missing something here. There I would like to know if someone smarter than me had cracked this 
