Spike's expression darkened when she pointed out what he knew to be a possibility. He may never get his gun back - or, if he did, it might be returned without ammo. Then, what? He'd break someone's skull with it... just to make a point about crossing him. That was what he'd do.
"Revenge," he answered simply. He didn't really care about going home, not enough to consider forsaking revenge to find an opportunity. And while escape appealed to his need for freedom, the situation had long since become personal enough that running wasn't an option. "Escape can happen later... Play it right, bite hard enough, and we could coax 'em into sending us home... Or killing us."
As always, Spike didn't seem concerned with the prospect of getting himself killed in the process. However, just behind the apathy in his tone lingered something... uncertain. His life was one thing, but his allies' lives were another - even if he wouldn't willingly admit such a thing aloud.
"We could make them think our goal is escape," he added with a slight smirk. It was partly the means of expressing an interesting thought and partly a means of pushing the topic in a better direction.