Stupid SH question 'cause my husband won't stop asking me

DrumminBeard wrote:

bluntcard wrote:
As I understand it, the bonus is for XP only and it doesn't show in your over all bonus amount. It's hidden.

This is correct; though it should be noted that 'maxing out' the level on each building isn't required. Just a Level 1 of whatever will add the bonus. The exception to this is the Private Island, which for some reason has to be Level 2 to confer its bonus.