Are you saying the cost of 12" of chipboard is expensive? Because it's not. Especially not at trade prices.
It's not blather, I'm not sure where you buy wood, but if you think the wood of bathroom door even makes up 1% of the cost of building a bathroom... And 0.01% of the cost of losing an employee to something so trivial as a horrid bathroom.
Honestly, this sounds like a US-specific problem, in the UK none of the offices I've worked in have had a 'gap' in the cubicals. Nor the schools or public buildings or public toilets.
Reading these comments are comical at how a whole country can collectively do something so simple so wrong. No judgement, every country has silly quirks like that!