Hmm my DD is a newly qualified VN and she did a section on business as part of her degree because VNs are often expected to take on some of the running of the practice - which is a business - and they need to know what they're doing or it'll be chaos both for the customers and the business.
I don't think you can blame vets solely for wanting to make money by keeping animals alive - it's more to do with the owners, vets have to give all the treatment options that are viable clinically, so the client can make an informed decision, and there's a culture of keeping humans and animals alive because there's a belief that alive, in any state, is better than dead. I don't actually agree with that but I know people who do believe it, and believe so strongly.
A friend recently had a dog collapse and it ended up being really serious, I went with her and the vet explained the options, candidly with the survival rate for treatment being 10%. She seized on that, the vet can't tell you what to do, only offer the options and the treatment was an option, just with a very low survival rate, but of the 2 options, that one was the only one that had a survival rate at all as the other was euthanasia. She seized on that and time was of the essence, so she was pressed to make the decision - not because of the vet, but because with every hour that passed the dog deteriorated. She chose PTS after we had a conversation about it and I think it was the best option, as she does now, but had she taken the treatment the vet would have to do it because that's what she wanted and was a clinical option. She seized on it because it would delay what happens to every dog owner one day, they lose the dog and people don't want to face that. The vet would have to have very strong grounds for insisting euthanasia is the only option, it might be the best option, but the client needs to be aware of all the options or they stand to be misinformed and that can be malpractice on behalf of the vet.