I could see that logic in full flow during my retentions call.
I was offered £80-90 price range (cant remember exact now) to stay as I was which was 500mbit boosted to 1 gig with O2. This would have had no cost to VM, as equipment was here up and running. I was already provisioned, just an adjustment on my bill.
I was also offered for £40-50 price range, gig1 boosted to 1 gig with O2, and a TV package, this had additional costs, which would involve TV equipment, provisioning of new service as well. Yet despite this, they would sell it to me for less.
Their logic never considered the cost of losing me as a customer, it would mean zero revenue. The worst out of the 3 scenarios. A 4th scenario would have kept the revenue stream going with the only thing would need to do is a billing adjustment. That was to leave me going on the same deal they were offering to some other customers. I would have accepted circa £35 a month for 500m boosted to gigabit with O2 sim. They were capable of offering it as some were getting it. For reference they lost the O2 revenue as I cancelled the sim not long after service was terminated.
To me logic is if you are prepared to offer someone a price to keep them as a customer, then you should offer it to everyone who is in the same circumstances. As otherwise you run the risk of people talking to each other about their deals, and people leaving because they dont get access to the same pricing, and I expect VM have had a fair bit of churn for these reasons, and I also wonder how much money they have lost forcing services down peoples throats that they have no interest in because as you said the obsession with multi play.
If no one gets these retention deals, aka everyone is treated the same, then people like me would be less likely to leave, as indeed I pay AAISP much more than I paid for my new customer price on VM, but because I know its the same for every AAISP customer, it is ok.