There isn't really enough incentive today in many cases, but there isn't a disincentive either. Institutions may not be keen on spending a lot of money on their patients' happiness, but they're more likely to get new patients if it looks like they're caring for their existing ones; thus, they have incentive to care for patients at least to the extent that doing so doesn't increase costs.
By contrast, adding "right to die" to the equation creates an incentive to deny patients event those comforts which would have no direct cost, since making the patient happier may cause the patient to stick around longer.
Remember, life is something an individual person has...the person isn't just a life. Let's be pro-individual, and not just consider only one aspect of each person.