I am eligible for Social Security but I am not drawing benefits yet. But I do file and pay income taxes. For the past two years the IRS has drawn cash from my checking account for taxes due; and Medicare has drawn cash payments for my premiums from the same checking account. So "they" certainly know where my account is!
But, like you, I had to enter my account information yesterday on that IRS "tool" page.
I am surprised I had to do this, but like my Uncle Rit used to say "Big Whoop!" I mean, it's a big honkin' bureaucracy, stuff slips through the cracks. Big Whoop.
Actually, I'm surprised that retired people on Social Security are getting stimulus checks. We are (in principle) continuing to get Social Security checks every month, no hang-up there, no interruption in our income. We're not losing our jobs, as so many other younger people are. We're not having to shut down our businesses we own (well, I suppose some of us may have to do so, but in such event I believe there are other stimuli programs for this event).
So it seems that the stimulus cash for retirees is not something to assist on a humanitarian level as for a natural disaster...hurricane, etc. but is instead simply handing out dough to spend in order to stimulate the economy (but why? we can't spend it anyway, the stores are closed! lol), with someone else down the road of time having to pick up the tab; maybe my grandkids ("Thanks, grampa!").
I don't know if this is right or not. I myself tend to be a very politically liberal person. But this case of stimulus for retirees who have not "lost" anything in this pandemic? I am not convinced that it is the right thing to do.
I haven't received mine yet but I spent just about that amount of money over the weekend sending donations to food banks and other charities to help them through this time.