If the boss says - even casually - something is their favorite shade of blue - I can almost guarantee that this shade of blue will magically start appearing in design, mock-ups, and copy proofs.
Why? Because in a power vs. trust leadership culture, people will search and cling to anything tangible in an attempt to make a power leader happy.
If you're brave, you can test this out. Next time an off-handed comment of preference comes from the C-suite, don't follow the indirect cue and go with red instead.
And if this makes you nervous, then you've learned what kind of culture you're working in today.