Hear-say (from the photo discussion area on ECN
, rather than personal experience: for a short stub of pvc from underground to the meter pan, the thermal expansion will not be enough to matter. Thermal expansion and contraction shows up as a percentage change in length, so the shorter the 'nominal' length, the smaller the change produced by thermal effects.
However the expansion joint will also nicely accommodate things like the soil settling after construction, or the earth moving for other reasons. If you search in the Photos Submitted for Discussion area, I'm sure you will find pictures of residential service stubs ripped out of meter pans by the ground settling.