All three care homes I've worked in, in the last 15 years have provided good quality nutritious food. All residents are weighed monthly to check that they aren't loosing of gaining excessive weight. Residents are monitored and food and fluid charts are used to record intake if there is a problem. Residents are always encouraged to eat and drink as much as they want/need. They are helped to eat as necessary and spoon-fed if needed.
I haven't noticed this happening in the hospitals I've had to go to during that time. There the food is often left out of reach of the patients and then taken away uneaten.