Should public assitance pay for drugs, wide screen TVs and fake fingernails?

Money is a fungible asset, meaning it can easily be swapped for something else. Public assistance supposedly pays for necessities the recipient cannot afford: food, housing, etc. That makes perfect sense. However, in my area, the people who are on it, in general, are the ones doing drugs, have unlimited cell phone plans and manage to afford (scary, IMO) nail treatments and other extravagances that require funds. Does that mean the assistance payments are too high? Should they be reduced?
Just to set the tone. I guess you’d call me liberal of sorts. It’s just that I happened to be in court (for someone else) the other day and watched other individuals entering, waiting and leaving and noticed some trends that I believe are statistically significant. For example, I pay for my cell phone and am careful with minutes. The other people were jabbering about nothing for long periods. How do they afford it? Why can they afford it if I am paying for their housing?