My non expert opinion is that you need a xanax... Sounds like you are in the right but your anger and bitterness over something as small as a free breakfast and **possibly** a better room assignment is astounding. Lots (probably millions) of people have had similar or worse issues in this merger/integration and surprisingly they have survived. Coming on here and threatening to move your nights is silly, why would we care?. Move them or quit crying about it. Sometimes patience is what is actually needed...even though it isn't fun. Sometimes voting with your wallet is the right way to go as well. I had an issue that started on 08/17/18 and wasn't resolved until mid February... I did 135 nights in 2018. I've done 7 this year and 6 of them are after the fix I needed. I may or may not get to 100 this year because of it but it was worth it to me to get the resolution I wanted.

Years ago I was in Kelowna, BC trying to fly home through Seattle... Somehow I found myself without a passport or Birth Certificate and the Alaska rep wasn't going to let me board the plane. My traveling companion started to berate this gal who was probably making just over minimum wage. I told him to shut the F*#$ up and leave her alone. Eventually I got on that plane. If you have treated the CS people at Marriott in the same manner you have used your words here it's no wonder your "problem" hasn't been solved.

Treating people with kindness will always get you further in the long run than arrogance and condescencion.