The most high-need, high-volume job offers traditionally come from these roles:
QSFB
Attractions
Custodial
Merchandise
Lifeguard
Depending on the season, Seater (FSFB) can also be considered high-need. BBB/PL and anything in the entertainment line of business is typically low-need.
Speaking from personal experience, it's worth noting that if you put "high interest" in Lifeguard and discuss it, even briefly, with your interviewer, you will most likely be offered Lifeguard.