fyo, they're not really the "backups" per se because the #3 (and sometimes #4) corner is on the field for nickel and dime packages. Its not like you have to wait for an injury for them to get burned by a slot receiver
I realize that they see the field more than, say, a backup quarterback... (although plenty of backup running backs and tight ends get lots of playing time)... the point was that Daniels was 5th or 6th in a position where 5 are usually kept.
This wasn't some good player or "potentially" good player getting cut lose. This was bottom-of-the-barrel churning.