When using globs and os.Args without quoting the target, the glob will match any files in the directory.

[pkar]

 $ go run cmd/ron/main.go t -default=target/default.yaml -l b*
 [/var/folders/rs/0jn_2dpn36x53x8tvgvptr740000gn/T/go-build477108253/command-line-arguments/_obj/exe/main t -default=target/default.yaml -l bin]

$ go run cmd/ron/main.go t -default=target/default.yaml -l "b*"
 [/var/folders/rs/0jn_2dpn36x53x8tvgvptr740000gn/T/go-build906759632/command-line-arguments/_obj/exe/main t -default=target/default.yaml -l b*]