Sanspo has an interesting little article on what happens to team equipment during spring camp. I won't go into a full translation, but I'll mention a few key points to the article:
The article uses the Chiba Lotte Marines as an example.
They shipped 32 tons worth of equipment to Ishigakijima, Okinawa for spring camp.
Lotte equipment manager / BP pitcher Shinichi Nagasaki told reporters that the team basically shipped everything, other than the cages used during BP, to their spring camp location.
16 tons of items, including 9,600 baseball and 7 BP machines, where shipped to Ishigakijima by boat on 1/14 out of Tokyo Bay. The equipment arrived on 1/26 and everything had to be set up over a 2-day period.
16 tons of player luggage was gathered together on 1/26 and shipped out of Tokyo via air mail, arriving in Ishigakijima on the 28th.