While social insurance like Medicare and Social Security should not be means tested, anti-poverty programs like food stamps and such should be. Anti-poverty programs like that exist to uplift people from poverty, not just give anyone a stipend so they can be lazy and not do anything. So yes they should be.
Means testing to receive government benefits is not only reasonable but necessary. There are many who rightfully need government benefits, including the elderly with small pensions, the poor and unemployed, but there is little control over abuse of the system. Means testing would be beneficial in cost savings and would allow more eligible people who need the help into the system, as well as remove people who are abusing it.