Southwest sends 4 drink coupons to Rapid Rewards members after each set of 10 one-way paid (not points) flights. To check that you are "opted-in" to receive them, log into your account, and look under My Account > My Preferences > Travel > Extras, and it should look like below (if not, choose Edit and update your preferences.)
Chase stopped sending coupons to cardholders annually, and now they currently send them on "milestone" anniversaries (every 5 years, reportedly.)
