You can work in academia under a limited clinical academic license (might vary between states/provinces), however I don't believe most private practices will hire a vet who hasn't passed the NAVLE because they wouldn't be able practice independently.
I think most things you could do with a DVM but no license are things you could do with other advanced degrees (PhD, etc) that would cost substantially less to achieve. If your goal doesn't -require- a veterinary license it is definitely worthwhile to look into the other options; if you can't practice medicine, getting a degree focused on medicine may not be the best use of time and money.
I think the kinds of things that are out there would be with USDA/government wildlife management, etc. Research as well, but it would depend on the kind of research and what your role is because you can't do certain things without a license, and you may need a PhD anyway.
[This is mostly conjecture because we don't really discuss what you can do without a license at my vet school]
You can't get a licence to practice in the US, so you can't practice veterinary medicine..........usually means you can't diagnose or treat an animal. So, you could work in management, and in any assorted industries related to veterinary medicine (unless those companies require you to have a license - some will, some won't).
Technically you can be a pathologist while not officially licensed to practice medicine. In many states anyway. It's ambiguous as to whether pathology is actually "practicing" medicine. My employer's stance is that as a clinical pathologist, as long as I call my bottom line in a report an "interpretation" of a sample rather than calling it a diagnosis, it's not actually practicing medicine (defined as 'diagnosing and treating animals') because it's up to a vet to decide if they believe my interpretation and they are the ones that actually put together that interpretation with the clinical picture and make the diagnosis. But to me that's a technicality and I am licensed in the state I am working in to be safe.
But really, a few pathologists I know who aren't currently holding a state license did take the NAVLE or some other board exam prior to their pathology specialization, they just haven't maintained the certification for their state licenses. It's not like they just said, meh, I don't want to take NAVLE so I'm going to get a hard residency and take an even harder exam with a worse pass rate instead.
You can work for USDA as a veterinary medical officer. FSIS and APHIS I know for sure will allow it, with FSIS being more willing to hire someone without a license / not having passed the NAVLE. They both prefer their vets to be licensed if they are working directly with animals, but it's not a requirement.
My understanding is that, as a federal agency, USDA employees are exempt from state licensing requirements if they are conducting offical duties on behalf of the federal government.