One really good reason to use the Beam or Arc is if you want to send the TV audio to other Sonos speakers, you won't have their inherent delay, which will show up as bad lip synch.

I have posted about this in other threads, about a job where I had installed Sonos connects and an amplifier for the outdoor speakers over/under their deck and at the fire pit, then the homeowner went to another dealer for their outdoor TV, had problems and called me to fix them. If this guy had said something earlier, it would have been possible to avoid the problems with the network, but the project is done and landscaping isn't going to be disturbed.