Every few weeks I go to the bank to get $300 cash from the money machine, they started giving only $50's when I want $20's because, for me,  it is easier to pay people for miscellaneous things.  Now I simply go to the drive up teller and ask for $20's, without fail, every time she asks "wouldn't $50's be more suitable?".  I always respond that if I wanted $50's I would go to the machine or ask for $50's.  Screw them, I want $20's.