Im low income, and my daughter paid for my first sub to sam's that was now amost two years ago. The difference it made in my month to month shopping was quite utterly amazing. Instead of running out of food the last month (and dishsoap and toilet paper) I began seeing my food supplies and non discretinary income get me through the first week of the next month. Im very careful, but i found that the expense it takes to buy things in bulk is paid off with in the first month, the peace it gives you knowing you have enough food to the next SSI check and the knowledge that the food you're buying is also very good quality.