The processing times for domestic credit cards versus international credit cards versus debit cards are very different. It's all processed by properties the same way but a lot of people only use debit when they travel and the processing times on that type of card is always significantly longer then using credit.

Regardless of what loyalty program you want to talk about, John Q Public has next to no idea about how anything works in the industry from the benefits and devaluations of the parent company's loyalty program to whether the property is franchise owned/corporate managed or franchise owned/franchised managed or the rare unicorn of corporate owned/corporate managed. To the overwhelming majority of the travelling public you're just staying at "The Marriott" or at "The Hilton".

99% of reservations are made via a channel that is directly affiliated with the parent company and not directly with the property which is why people start there for any type of problem resolution. There is also prevailing misconception that if person X contacts corporate, then somehow they will expedite things or roll over the property to make a resolution occur faster which in 99.9% of cases couldn't be further from the truth.