Ah^ Very good logic there Zerker, but what if you get reported for something more serious?
Well if you got caught buying or selling gold lets say, and you were reported, then yes there is a chance that Jagex could investigate your account for that very reason since you have allegedly been involved in RWT.
Still - there are many precautions you can take to avoid getting in any trouble if you
did happen to be reported. Try to trade in areas that are not heavily populated, use safer methods of transfer like staking the gold over or gambling with it (dicing and flowers etc.), and distribute your extra wealth among several mule accounts if you have alot of wealth. This should minimize your chances of being wiped by not providing Jagex with solid evidence if they DID happen to investigate your account.
With that said, your original question is regarding the possibility of being banned. It is always up to Jagex's discretion on whether or not the offence warrants a ban, but it is becoming increasingly rare for players to be banned for offences like RWT & botting. Jagex has abandoned their old "tough on rule breaking" stance and has softened up a little, instead focusing on targeting the larger players in the black market - such as major gold sellers or people who are running very large botting operations - and issuing wealth wipes and rollbacks for regular players who are caught cheating instead.
So yes, is IS possible you could get banned if Jagex were to investigate your account and had direct evidence you had recently sold/bought 50M GP. But it is
highly unlikely. Just be smart and familiarize yourself with ways you can trade as safely and inconspicuously as possible, and you should be OK
Hope that helps!