No doubt, many through that time and since have sold their possessions, sacrificing life for the "sake of the good news". The thought was (except the disingenuous ones who thought about Armageddon would cancel their debts) that moving for the preaching work was supposed to mirror the first-century disciples and hence be a career approved by God. To be honest, though, much of the motivation was surrounding gaining everlasting life on a paradise earth, as opposed to "vindicating Jehovah's name." That's what I thought about, too. But deep down, I found it hard to imagine living with myself in a luxury home I had not bought, paid for, or built, at a "worldly person's" expense, in the "paradise earth" after Armageddon.
In Ray Franz' books, I appreciate the more pure motivation of larger universal issues, which bore out well in what he wrote.
When you have a conviction about something, it's easy to cut off in one's mind any other possible outcome, and just adamantly "root for the truth". It's bloody hard to shake that kind of thinking.