Because he can

[j.p.]

and robbing the senators of a clear win on the stimulus.

Yeah, who would wanna rob the Senators, Egypt, Sudan, Pakistan, horse track owners. American citizens would get a whopping $600 bucks and illegals would get $1,800. I can hear those poor bastards now, "WE WUZ ROBBED!" FU

If there were any non petulant purposes for this, I would agree. Trump did not participate.

I am against stimulus that don't stimulate
I am against welfare for everybody
I am against gov't effectively forcing future generations to pay for this nonsense