You are correct in that I insist on injecting a note of reality into the discussion. Saying that 'I don't agree with the premise of (insert issue: welfare moms, providing disability paychecks to middle-aged white males with spurious claims, etc)' as if that should solve the problem ignores the real world. These things do occur and have to be dealt with in the real world. To try to dismiss that is handwaving at its best and is an informal fallacy.
Anyone who states that (welfare moms, providing disability paychecks to middle-aged white males with spurious claims, etc.) is not the taxpayer's problem is choosing to ignore the reality of the situation. We can certainly argue and disagree on the scope, nature or origin of such problems, but to pretend they don't exist, they don't have to be addressed or you can make them go away by 'disagreeing with the premise' is ludicrous.
Don't just bitch about the problem, come up with solutions.