It's a metaphor and it can definitely be taken too far. One of the abuses I don't care for is the notion that Technical Debt can be quantified and calculated for a code base. That's wrong in a number of different ways.
Why does the sales guy get to go play golf after closing a big deal? And yet the developer still has to show up and sit in his seat after he performs some equivalent wizardry? Because the sales guy's effort has a number attached to it, that's why.