I hear you bringing up 2 separate actions that can trigger a registration requirement.

1) Garaging a vehicle, for x days or more.

2) Driving a vehicle, for x days or more.

Have you looked into what the specifics are, and how they are triggered?

Poking some holes at this:

- Are you on the hook to register vehicles you don't own for actions (1) or (2)?

Consider two examples:

(a) you rent a vehicle,

(b) you drive or choose to house a friends' vehicle.

From what you've stated, logically, anytime you rent a vehicle or operate or house a friends', you now are asked to register it.

Do you think this is accurate? And if so, do you think it would hold in court of law?

>Consider two examples:

(a) you rent a vehicle,

(b) you drive or choose to house a friends' vehicle.

in both cases, the vehicle would already be registered in the state (by the rental company or by the friend).

it is not clear to me why you think the vehicles would need to be re-registered.