When I had a shop open, I had regular visits by a couple who collected different things. He collected trains and she collected anything that said “NOEL” on it. The fight that they might have over the pictured item could have been memorable.
This illustrates what the term “cross-collectible” means. The item fits into two collectible categories or “crosses the boundaries” of two types of collectors. Hallmark takes advantage of this regularly in their series–the Star Trek vehicle series being a prime example. Attactive to the Star Trek fan and to the space vehicle collector.