I'm pretty sure I read this in Analog, in the early 1990s. As best I can recall the story is set on Earth; technology and society are not greatly different from current, except possibly for a certain amount of imported alien tech.
The aliens came to us, but are essentially driven by commerce. They will sell us services and maybe some technology, but there must be a bargain-a contract-and some quid pro quo. I don't believe this is the same universe as the stories where the aliens are economic fundamentalists who have essentially forced the shutting down of all of Earth's governments and social structures as monopolistic enterprises. The aliens are content to let us run the Earth, and just want to make deals.
The viewpoint character is a wealthy businessman, probably a financier or the like. He has a fancy office, and every day he enters the building past a panhandler who he occasionally gives a dollar to. I believe there was some history between them, like they both served in the same military unit. He looks down on the panhandler, but still has some residual kinship.
The aliens seem to lack proprioception; they are described as moving jerkily, like poorly controlled marionettes. Their gaze is constantly darting around, watching the position of all of their extremities so they can move them properly. If I recall correctly, they have devices that allow them to jump anywhere on Earth.
After a fair bit of wheeling-and-dealing, the main character finally convinces one of them into a bargain which, on the aliens' side, requires them to remove from Earth everyone who is non-contributing. He eventually realizes that will include the panhandler and calls down to the front desk to tell the panhandler that he should be considered part of the organization, but it's too late, the panhandler has been vanished.
The main character then reads or realizes that the aliens visualize their bodies differently from us; almost as though their bodies were other and controlled like puppets with strings. So when he made his bargain with the aliens and told them it was "no strings attached" they would have interpreted that to mean that instead of just disappearing people they were actually supposed to kill them.
The story ends with an alien appearing in his office, telling him that they've come to the conclusion that his job has no benefit to society.