Don't all airlines do that though?
Yes, of course, but we've also seen cases at SOU (BRU springs to mind), where BEE came onto the route (which Eastern were on at the time), forced them off with cheaper pricing, then dropped the route as commercially unviable.....which is of no use to anyone.
SOU-LBA has seem the same happen in the past, but Eastern have been back on that route for a while now and seem to have made it stick.