I could see doing it 'just this once,' for an emergency - but then you get away with it, and next time it's a little less of an emergency - and eventually, it's

I could see doing it 'just this once,' for an emergency - but then you get away with it, and next time it's a little less of an emergency - and eventually, it's just "hey I want more money" so poof now more money magically appears for you.