aws s3 sync does not synchronize s3 folder structure locally

The aws s3 sync does not fully synchronize the S3 folder structure locally even if I use it with --delete or --recursive arguments:

aws --version
aws-cli/1.4.3 Python/2.7.6 Linux/3.13.0-35-generic

$ aws s3 ls s3://s3.testbucket
$ aws s3 ls s3://s3.testbucket/
$ mkdir s3.testfolder
$ mkdir s3.testfolder/test1
$ aws s3 sync ./s3.testfolder s3://s3.testbucket/
$ aws s3 ls s3://s3.testbucket/
$ touch s3.testfolder/test1/1
$ aws s3 sync ./s3.testfolder/ s3://s3.testbucket/
upload: s3.testfolder/test1/1 to s3://s3.testbucket/test1/1
$ aws s3 sync ./s3.testfolder s3://s3.testbucket/
$ mkdir ./s3.testfolder/test-to-delete
$ aws s3 sync s3://s3.testbucket/ ./s3.testfolder/ --delete --recursive
$ aws s3 sync s3://s3.testbucket/ ./s3.testfolder/ --delete
$ ls -lah ./s3.testfolder/
total 60K
drwxrwxr-x 4 tobi tobi 4,0K szept 12 15:24 .
drwx------ 71 tobi tobi 44K szept 12 15:22 ..
drwxrwxr-x 2 tobi tobi 4,0K szept 12 15:23 test1
drwxrwxr-x 2 tobi tobi 4,0K szept 12 15:24 test-to-delete

$ aws s3 ls s3://s3.testbucket/
PRE test1/