Three of Cups - Four of Wands
to date and marry
to date - Three of Cups
and marry - Four of Wands
Three of Cups is a snapshot of some girls enjoying champagne together, all dressed up, so this is the card that shows up for the dating scene.
Four of Wands is a wedding, the outdoor public celebration of a wedding of the town's leading families, so it is the main card for marriage.
(This spread says about the same thing in a different way. Four of Wands is the VIPs, the wealthy or influential class...