If that's the case, why isn't Sony suing Studio Canal? The proper license for Sony to get is one which doesn't allow Studio Canal to take it away after sale in any way. So did Studio Canal somehow hack into Sony HQ to violate that license, or did Sony simply screw over its customers by not getting the proper license in the first place?
They're both to blame. Studio Canal insisted on a licensing agreement that works this way, and Sony agreed to it to sell their content.
For Sony, the correct move here would have been to not list Studio Canal titles in the first place, and put out a very public statement saying that they aren't being listed until Studio Canal agrees to make purchased licenses perpetual as they should be.
Correct. In theory, Sony should have warranted that they have the rights to sell the thing the way they sold it. If they didn't have the rights to sell a movie perpetually, then that's on them.
Not wishing to let them off the hook, but consumers did not enter into a contract with Studio Canal, so it's somewhat irrelevant to the actual issue. Sony willingly entered into a contract with Studio Canal and then "sold" items to consumers that they could reasonably foresee would be time limited without making that clear to the purchasers.
I'd like to see Sony executives put in prison for fraud for this.
If that's the case, why isn't Sony suing Studio Canal? The proper license for Sony to get is one which doesn't allow Studio Canal to take it away after sale in any way. So did Studio Canal somehow hack into Sony HQ to violate that license, or did Sony simply screw over its customers by not getting the proper license in the first place?