This isn't actually true. Those who have more income spend much more money on drugs.
I used to smoke weed all day everyday for 10 years, and knew a ton of others that did so. None of us were poor, all had good jobs and made good income.
Moreover, people that only smoke rarely and have never smoked get the wrong impression about what smoking all day does to you. I would hardly call it being 'stoned', more like being slightly buzzed and less anxious. I don't think anyone who didn't know me would have ever been able to tell, unless I smelled like weed or something.
I now don't smoke at all, and the difference in experience is pretty minimal. I feel about the same as I did when I was smoking constantly, which is a testament to the powerful ability for neuronal self-regulation in the brain; both on and off drugs.