The complaint from the right is that the federal government confiscates the wealth of its citizens and redistributes it, presumably suboptimally. Leaving aside the objections to coerced wealth redistribution, there are questions of inefficiency, corruption, fraud, etc. i.e. One can easily imagine that a free market in social services would result in a more prosperous nation.
In any case, I think the right does not distinguish between Social Security, Medicare, and other entitlements in its objections to a spendy fed.