> Even a green card holder can be denied re-entry on the basis that they 'abandoned their residency.'
If you're actually living in the US and just taking occasional vacations abroad this is extremely unlikely.
Where people get caught out is when they're trying to basically snowbird between two countries while still on a green card. In that case it's better to first serve your 6 years in the US to earn citizenship. Then you're free to go anywhere anytime you want.
If you want to 'snowbird' like that without waiting for (or ever planning to get) citizenship, you can apply for an I-327 Re-Entry Permit. [1]
You can apply with form I-131 and like $575.
While it can take 3-12 months to process, if you apply more than 60 days before travel and complete your biometrics appointment, you can leave and pick it up at a foreign embassy or consulate. This helps you avoid the presumption that you abandoned your US residency.
Very true. But the point the OP is making is that your entire fate is in the hands of a CBP officer and they are a very, very mixed bunch.
I repeat OP's advice to avoid a land crossing, I'm not sure exactly what it is but I suspect partly that land crossings have much less time pressure. I've had my car pulled over and partly taken apart looking for "anything suspicious". We were two men in our mid twenties and I think the agents were just bored, honestly.
If you're actually living in the US and just taking occasional vacations abroad this is extremely unlikely.
Where people get caught out is when they're trying to basically snowbird between two countries while still on a green card. In that case it's better to first serve your 6 years in the US to earn citizenship. Then you're free to go anywhere anytime you want.