You only think you have no data caps until you start blasting your ISP with non-stop video that doesn't buffer.
On my isolated NIC, my cameras are streaming non-stop 450Mbps worth of data. This is full-on, never stopping to take a breath. Even if someone has a gigabit router, a 3rd of non-buffering 24/7 data will impact its speed and slow your internal system down.
And the ISP will take notice of that non-stop data that doesn't buffer.
I recently moved a few of my cameras to a neighbors house as they had better site-lines for plate reading cameras.
They are on 1gig service with no data caps.
I had 3 cameras sending over their internet mainstream back to my house.
Within days, their ISP told them they had to cut devices called LPR1, LPR2, and Overview from their system or they would cancel their internet.
Now what is scary is how did the ISP know the names of the devices.... yeah we know it is their internet and blah blah blah, but it shows why people VPN because the ISP can see what is happening.
Plus the whole point of BI is to have local control and not be dependent on any outside cloud or other systems, so I doubt anyone would do this.