Multi SQL Server Web licence on Single Machine
Apart from the licensing question, there's a question about the technical limitations of Web/Standard edition.  

Web edition is limited to "Lesser of 4 sockets or 16 cores", but for a Virtual Machine the sockets and cores are reported by the hypervisor, and may differ from the underlying hardware.  That appears to be the case here, as the hypervisor is presenting the VM with 8 VCPUs and claiming that they are on 8 separate sockets.  

SQL Server on startup looks at the reported sockets and cores when and will limit the schedulers accordingly.  Here that's limiting the CPU use to half of what it should be.

To fix this, the hoster should reconfigure the hypervisor to accurately report the socket and core count of the hypervisor host.