It seems like that changed somewhere around the turn of the century, whereby businesses started to decide that it was better to cut down on customer service, and in some cases, go so far as to ban customers. The first cases of this I recall reading about had to do with Best Buy, and specifically their policy of banning people from their stores who made a lot of returns.
I'm not really sure how it ultimately maths out - i.e., whether it's long-term optimal to drop troublesome customers or merely short-term optimal, and this was primarily taken from the perspective of retail.
As such, I'm sure the math changes a little for subscription services. However, I also recall my prior employer's support activity followed a power law distribution across its clients, so it wouldn't surprise me if a policy to drop particularly noisy clients is a net savings there as well.