I believe the appropriate idiom here is: "Don't look a gift horse in the mouth".
The winners apparently write both the history and the idioms. The Trojans would have done well to look a gift horse in the mouth.
A wooden horse can be full of physical soldiers and a digital horse with legal ones.
The idiom could be modernized to: 'dont check the odometer of a gift car'
In the case of other "gifts" the value can be negative. The trojan horse, software, and blankets from Lord Jeffery Amherst all need careful examination.