“fake developer accounts” (for remote work, which is all we do) collecting paycheques until fired,

I remember reading a story on such an incident. But honestly, I thought it would be something extremely rare.
Because, how does someone get money without providing work? And if they are giving actual work, then does it really matter if they are doing it themselves or making a bot do it? (despite it possibly requiring much greater effort to make a bot do a person's job well enough)

On the other hand, I see it being possible in case managing party doesn't care about whether or not the work is being done, for a long enough time, but can't the fake worker be caught and dismissed before the payment period in that case?
I mean, in my case, after working for the month, I have to submit a time-sheet and get it approved by the project manager and if they say that the work I have done doesn't justify the time I state, they can simply refrain from paying up and ask me to reduce the claimed time (and still keep the work I have given them (ok this part would be illegal if they don't pay me at all, but it's not like I can prove that they used my work)).

spying

This seems more viable. Industrial espionage and what-not. No idea how many sectors are competitive enough for anyone to consider this, though.

And then comes the point of interviews. Either it would be that the person has enough domain knowledge to clear the interview, or they are somehow getting lucky and not having to clear the interview (??feels weird saying that in the comments section of a post showing how hard it is to even get to an interview).
I feel it difficult to understand how someone would be able to get anything more than an entry level job, when they don't even care to work in the field. Some kind of master con-artist, maybe.