You'll see a lot of these types of playfields in older EM games. This is called "planking" where the wood starts to separate from environmental factors and, mostly, from lack of maintenance.

There's a ton of information on the Web, and Pinside, about restoring playfields. The Bon Voyage playfield in the example photo could be easily touched up since it has simple artwork. Basically, clean the playfield, do the paint touch ups, polish the playfield and then wax the playfield. This playfield would not be a candidate for a complete playfield clear coat, since there isn't much damage to the paint... Or just clean, polish and wax the playfield, and enjoy the game "as-is."