OP only knows what he saw/heard and can't possibly know the facts. Perhaps the other pax was a selectee for one reason or another and a positive bag match had been ordered for him (something the GA would not discuss with the pax or in public).
And, as to WX -- which is the most likely explanation for last night -- the pax wasn't entitled to compensation of any kind. It's just a risk of travel that there's bad weather and one is late.