What do the following words have in common?

HIP
LOB
BOO
MOB
HAM
SPIN
MOLE
TEAM

HINT:
Each word can be followed by the same four letters.

Answer:

Each word becomes a new one with the addition of STER at the end:

HIPSTER
HAMSTER
LOBSTER
BOOSTER
MOBSTER
SPINSTER
MOLESTER
TEAMSTER