I am actually now a recipient of food stamps, and from my experience, as long as you have used the bulk of your allotted amount to buy real sustenance, I don't think there's anything wrong with buying a bit of "happy food" at the end of the month if you have some left over money before the next month's money comes in.
I am 28, unemployed, uninsured, and by the middle of next month, I will have to start paying, somehow, on the student loans that got me through the past four years of college to get me a Bachelor's Degree that apparently doesn't do much to get a job, since I've not received a single call back on any of the applications I've sent out for jobs since I moved back to Kansas City. I am also suffering from cold urticaria (which is an extra pain now that the weather is turning cold), severe depression (and currently un-medicated because I ran out and can't afford to get more and am having to wait two-plus weeks for my free doctor's visit at the local low-income health center), and suspect that I have Asperger's (I don't have an official diagnosis because I haven't been able to afford to go get tested), the characteristics of which are a big reason I have a terrible work history because I deal with major social anxieties, among other things.
So, sure, there are people who abuse the system, but that's always gonna be the case. Thing is, the majority of those who are being supported are being supported because they have good reason to be. Try to tell me that I should not be able to get medicine for my depression or food for my stomach.