I used to buy knives for specific purposes, but sadly these days, those purposes are few, and I have way more knives than I'll ever be able to use (much less use to the point of dullness!) in this lifetime. So, I stopped lying to myself some time ago. Any knife I buy these days, it's merely because I want it. I haven't had much time in the past year or two for camping type outings, and my daily uses would primarily be eating, food prep, package/envelope opening, and thread snipping, which of course could be handled by nearly any knife.
That said, I have specific knives for uses that I don't currently have, to be fair. Zombie killin', chopping, animal processing, wood carving, self defense, beach days, and so on. The good thing about knives is that they don't have an expiration date and don't go bad!