Bale To ManUtd or Arsenal

I've seen a lot of these rumors. But I've seen little if any evidence at all showing that Gareth Bale has any interest in leaving Southampton. And the Saints are in the middle of a promotion battle and are not in desperate need of cash. More so, Bale still needs to work on his defensive side quite a bit. The big clubs may be interested but I don't they're serious about putting up big money for Bale at this point. And even if they were, there are no concrete signs that Burley wants to sell him nor that Bale wants to leave. Is this another example of rumors having legs simply because they would catch the attention of all those fans at those big clubs?