Originally Posted by
oldtora
.. If you purchase an economy ticket on UA for the last flight home on a Sunday .........
It was not the last UA flight home on that day. There was a later flight but Dr Dao was not offered a seat on that later flight, though it seems that he would have been prepared to accept that as an offer.
But in fact, they did not offer him a seat on that later flight. Nor did they offer him a seat on the following morning's flight; nor on the mid/late morning flight.
Nor did they offer to get him on any competitor's flights - probably understandable, but it was an option; to try at least.
That is precisely why and when he dug his heels in. Which is also when UA decided to execute their perceived next-best option.