Linode, and most alternatives, don't have S3/Blob storage as a service.. also missing are distributed key-value storage as a service and sql as a service.
Generally, with any given service as you can scale it makes sense to run your own instances.. but realistically someone who knows insert-tech better than AWS/Azure admins is a pretty rare breed, and having to in-source those specific skills costs in terms of time and money, redundancy even more so.
If you have a team of 3-5 people, you can do far more with AWS or Azure than you can most alternatives... Employees aren't free.
Generally, with any given service as you can scale it makes sense to run your own instances.. but realistically someone who knows insert-tech better than AWS/Azure admins is a pretty rare breed, and having to in-source those specific skills costs in terms of time and money, redundancy even more so.
If you have a team of 3-5 people, you can do far more with AWS or Azure than you can most alternatives... Employees aren't free.