It is common for multi memory hearing aids to have three or four programs available. Your hearing professional should only activate them as necessary.
Personally when I fit a multi memory digital aid I activate only two programs, one for normal use, and one for background noise situations. If a patient has areas in their life that they still struggle with I add additional programs.
Lazy specialists sometimes just leave three or four default programs active that the factory programmed. This seems like a bad approach to me. I like to keep it simple, unless my patient indicates otherwise. Only a small handful of my patients use more than three programs.
As for your comments on Starkey, I don’t see any evidence that Starkey has any more issues with feedback than any other brand. I’ve fitted many different technologies and I don’t believe it is fair to suggest that one brand is any more susceptible to feedback than another.
Now, within each brand some models ARE more susceptible to feedback than others. A good hearing specialist should take that into account when considering your loss and the specific model of aid he or she is going to recommend. It is not a brand issue, it is a model issue, along with a few other factors.