Here is my take beacuse I know Pumbas is waiting out there to hear it...
Garages can be done with pleasing aesthetics as will be seen at DS. And of course there is nothing visually intrusive about a sea of cars as far as the eye can see.
What I think would make sense is a number of garages for an upcharge and possibly AP'ers and Diamond parking. Valet parking could also be offered. That way they are revenue neutral at least and would allow for DAK to expand in the future. Also, more garages translates to less trams. Diesel is expensive and pollutes.
Garages can have solar panels. So garages can be the green option.
And those that are mocking the move as being overconfident, perhaps there are additions in the works that have not been announced. DAK already needs more parking on some days.