Both sides are using the same options within the battle mechanics. I'm not sure this is called an abuse as it was an intentional part of the battle mechanics if I recall correctly. If one is to blame, I believe I was the first to implement this strategy 1.5 years ago or so already. Oligarch required any edge against Sirion and so we used some different settings and tactics including this one as I noticed this archer behavior when analysing some battle reports.
If you want this changed, I suggest you make a feature request on this forum and hear what the devs have to say.
As I see it, this part is not a bug, but an intentional decision and thus you should be able to use it. Sirion leaving regions rogue goes probably even further than this, but that too is a concious decision well within the boundaries of intentional mechanics and I see nothing wrong with it from an OOC perspective.
