It's a fairly simple equation: What's the thing you'd have to do (or stop doing) in order to receive (or not pay) the money?
You can argue about whether imposing a financial disincentive on working is a good or bad policy but there isn't really any case to be made for it not being what they're doing.
My point was your initial premise is wrong: “All of the funding comes from the taxpayers, and they're the same taxpayers”. There’s plenty of instances where the federal government takes and redistributes tax dollars, from person to person, or state to state. Calling this particular instance a fine, but not every other instance, is wrong.