This type of infringement is a great example of why trademark registration is so important. This also perfectly illustrates the core tenets of what a trademark is.
Section 2 of the Trademarks Act defines a trademark as "A mark that is used by a person for the purpose of distinguishing or so as to distinguish wares or services manufactured, sold, leased, hired or performed by him from those manufactured, sold, leased, hired or performed by others". Essentially, a trademark is meant to distinguish the ORIGIN of wares or services - meaning the individual or organization who is providing those wares and services.
The foundation of all brands are built on the reputation they've established with consumers. The reputation of a brand speaks directly to the origin of the wares and services that are provided under that brand. This is usually the most important factor potential customers use when trying to determine level of quality of a certain product.
So why is Ford Motor Company concerned about someone else using their logo in an unrelated market? Because they have spent a great deal of time and money establishing themselves as a reliable, 'family values' type of company. When someone who is embroiled in a scandal of this nature appropriates their brand, it erodes those core values and ultimately impacts consumer loyalty.