3rd Rock from the Sun (1996)

S5E7 Sex and the Sally

Mary is appalled to discover that Dick has been taking all the tip money she leaves at restaurants. Confused about the purpose of tipping, Dick tries to create his own system by stacking dollar bills on the table, telling the waitress that her service will determine whether the pile increases or decreases. Mary quickly tells him that this approach is disrespectful. Meanwhile, Sally starts using the pill after Tommy warns her that she could get pregnant from her encounters with Don, but soon finds herself facing unexpected mood swings and unusual food cravings.