No argument from me about the cost associated with overgrown violins. I probably ought to put new strings on the doghouse, but they sound fine when replacements cost $600. I have a bag for it. The bag is protective up to a point. A fiberglass case would be better and would have prevented the need for a couple repairs. The repairs, combined, were cheaper than a case. Plus, a case is enormous. My bow is a plastic cheapo with horse hair. It is fine for what I do, but mostly inadequate for a person with actual skill and talent. It cannot be repaired. Once the hair wears out, it is done. I can believe that cello stuff is even pricier.
The case I'm looking at is 'semi-hard' -- quiet at the back! -- which is fine for my purposes and has the all important shoulder straps. It will also be slimmer than the plywood monstrosity.