It's because they're known quantities that can get good finishes. A quick check on Racing Reference confirmed my suspicion-
Out of the "core" Rick Ware cars last year...
BJ McLedod- 6 top 30s in 18 starts
Cody Ware- 1 top 30 in 13 starts
JJ Yeley- 9 top 10s in 15 starts
Ragan, Yeley, Timmy Hill, Tony Raines, Reed Sorenson- all guys who can take a 35th place car and drive it to 25th place once in a while. That's the job of an experienced backmarker. Their careers are as long as the Tony Stewart's and Jimmie Johnson's in the world- there's still a place for them in NASCAR.
They're definitely not talented. You could put a rookie in those cars and they'd wad it up in the wall each week trying to keep it a single lap down.