When your talking with a tire maker rep and you mention the vehicles tire placard psi/size/type/etc they generally will recommend what the vehicle sticker says.
Its a liability thing.
Now if you don't mention the tire placard then the liability issue isn't there anymore and they generally can give you their recommendations.
Just another example of folks with tons of experience such as a forum using the product can give better input to new folks than a tire or vehicle rep. No disrespect to a rep as they have to be very careful what they say or recommend in this area.