I understand D+ is Disney's biggest revenue source or one of the biggest I forget the exact figures but I hate how much they push it everywhere. The blue carpet I looked up looks tacky, the HSMTMTS preview in Tomorrowland of all places, the weird Disney+ merch they sell, all of it is so annoyingly in your face and shameless. The parks have always been an advertisement for upcoming projects, I get that, but it wasn't always a blatant ad that added nothing to the park. If there was some beautiful structure built to promote an upcoming D+ project that genuinely looked good and added ambiance to the park I wouldn't care but that's not what they do.
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@Sharon&Susan said I wouldn't be surprised, it would be like the weird Target announcement they did previously and just feel wrong. Disney wants to promote their services to bring in even more revenue, sure, but if I'm already in the park dishing out hundreds of dollars to be there and enjoy my trip while paying for food / merch / etc. in the parks I would prefer not to have Disney shove a product I already subscribe to in my face in an effort to take even more of my money when I'm away from the parks too.
I haven't used the Disneyland app in a while since I haven't been since before D+ launched but I wouldn't be surprised if they have / plan to add advertisements for D+ into the Disneyland / WDW Experience apps.