Of course it is, it doesn't have access to your account!
I would give €900 per month as an average for the some 25 adwords accounts I've looked at in the last month - I dont do adwords, I'm not an expert, I'm not even going to try! but I know web marketing, everything I've ever sold I've sold over the web, since 2001. I've generated over €1million in sales for myself alone, and probably 100 times that for different clients.
I know 5 companies, all very small, who spend in excess of €15k a month. If you had a conversion ratio of 10% and a cost of €10 but made more than €10 profit on each sale, wouldn't you spend as much money as you could?