I don’t know they’d have to award you wages, but the only alternative to that would be firing you. Some might try to do that out of spite but it would be far worse for them than you.
i.e. if you get caught stealing or are sexually harassing your co-workers, they can still fire you. They are not however required to let you work. They can revoke access and continue to pay, they can give you a package and terminate you employment. If you don't want to take the package, they can just walk you out of the building and terminate your employment two weeks later.
I’d agree that most reasonable HR departments wouldn’t let it go that far but some people like to play dirty irrespective of the costs.
Many states pay significantly higher than $550. WA pays a max of $999 weekly.
Unless, of course, you are trying to collect during a period that is scheduled as a vacation? That could create problems.
As a former lawyer (US-based), my sense is the first is true, and the second is not. As long as they're not canning you for being in a protected class, they can fire at-will employees whenever they want.
Most employers get their unemployment insurance rate set by the number of people that require the service just like any other insurance. When an employee can prove they quit (probably before you started 'performance managing' for a with cause termination), then it makes it much simpler to just let them leave then to do the paperwork, eat the unemployment insurance adjustment, risk a possible 'wrongful termination' lawsuit (regardless of merit or ability to win).
Transferring their work and letting them dick around for a week is going to be considerably less work and risk then terminating them before the date. So as a general rule, when you give advance notice, in writing, there is a very good chance that they'll just let you leave on the day.
Additionally, if you fire everyone immediately when they give notice, then people stop giving notice all together, so you just come in some days and are a person short.