https://www.google.com/intl/en/chrome/business/solutions/for...
We've only hit this limit with very large all-hands meetings or presentations that lots of people also want to dial into. We often have a separate view-only stream for those cases.
Though, I believe both Webex and GoToMeeting charge extra to have this ability.
You're left off with XAMPP and OpenSource tech?
At a previous job the building next door was a remote office for a non-IT part of a large non-tech company. They spent the money to get some kind of carrier line (maybe EPL/EVPL?) solely for teleconferencing.
While the system is almost certainly not difficult to compromise for TLAs and others, they get assurance that the data hasn't left "their" network,
I personally don't think there's much rhyme or reason to that particular permutation of those policies, but there is certainly a large group of buyers who are fine with potentially backdoored commercial products as long as "the data doesn't leave our network" and hence would not be OK with Google's solution.