diversify
Good argument for diversification.
If you have a couple of hundred thousand in money market or other bank-deposit sorts of investments, I'd go to the trouble of opening accounts at two or three banks to keep most of the money w/in $100,000 insured limits.
I guess if you're worth many millions and your money market is just to have little pile of liquid assets maybe it's not worth the trouble, but FDIC insurance seems like a good enough deal that if $200,000 is a noticable fraction of your assets, why not open two accounts?