Why does Avast scan other public ip's?

I run a dedicated server with Server 2008 standard on it that is hosted by OVH. I run a virtual machine in virtualbox on it with Windows 7 Ultimate as the guest OS.

I installed Avast Home Edition on this to keep it virus free. Since the last program update I have been receiving warnings from my host regarding arp attacks from the ip assigned to the VM:

Wed Dec 3 00:24:56 2014 : arp who-has 46.105.231.251 tell 46.105.231.50
Wed Dec 3 00:24:56 2014 : arp who-has 46.105.231.252 tell 46.105.231.50
Wed Dec 3 00:24:56 2014 : arp who-has 46.105.231.253 tell 46.105.231.50

The IP was blocked once for the arp requests, and shortly after unblocking it, I recieved another warning.

I then opened a support ticket to try and get it fixed (thinking it was a problem with their network). They asked what I was running, to which I listed all programs running. After removing Avast as they suggested trying, they confirmed that the requests had stopped.

On looking online, I can see that this seems to be common with Avast.

The main reason I am posting this, is to hopefully make the developers aware that scanning a whole network of public ip’s is stupid at best, negligent at worst…surely avast could be coded to know the difference between public and LAN ip’s and only scan LAN ip’s?