I'm guessing it's not a matter of nickel-and-diming, but it just really being very unwise or totally infeasible to get global rights for everything. Of course, I'm just blindly speculating and I have no clue and maybe they really are being cheap in some way.
And I think it's quite possible the VPN stuff really is out of their hands. (From a policy perspective, not an implementation perspective. Obviously the implementation is entirely on them, and the false positive bans are their fault.)
From a business perspective, I would think they'd be incentivized to allow them and not dedicate resources to trying to block them. But lots of podcasts I watch have a bunch of ad segments for different VPNs, where the main selling point is typically "watch stuff for other regions on Netflix", and I'm guessing the companies they're licensing from are increasingly seeing this loophole as basically a form of piracy.
For example, say they want to license a show, and they get it for one year for $50k, usa-only.
Okay, but we want it world-wide. Alright, that will be 3 million, world-wide, except Australia. Okay. wait, what?
We have a 7-year contract on Australia right now. We can't give you Australia.
Now netflix has to decide if it's worth it for the 350 people who want to watch this in Europe and Asia to take the second deal.
Sucks.
To add insult to injury, they don't even bother showing the movies and shows that they lock up this way. It's just about exercising monopoly power.
If the VPN node's public IP matches the country in the subscriber's registration details, then it seems pretty unfair that they'd still restrict their account when accessed from that VPN IP. But I suppose from a technical standpoint it's probably far simpler for them to just find VPN IPs/subnets, add them to a database, and restrict content for any account accessed from any of those IPs, regardless of the account, IP, or content regions.
Suppose you are Canadian. Netflix has permission to sell Americans "Media Package A" and Canadians "Media Package B". They don't have permission to sell Canadians "Media Package A". You are saying "just let me buy both" but Netflix does not have permission from media companies to sell you both.
By that same token, I wouldn't be surprised if lawyers have been breathing down their neck for years trying to pressure them to crack down on region lock-bypassing VPNs, and perhaps even threatening legal action against them.
(Of course, that's not justification for blocking residential IP addresses as VPNs when there are non-VPN users behind those IP addresses. Just wanted to point out that the blocking policy is probably something they have to do rather than something they want to do.)