We had that at one store and then they got rid of it. I think the long looking queue put people off but it moved so quickly. Was much more efficient.
I remember Frys Electronics (RIP) used to do that.
Kohl’s, Barnes & Noble, Ross have single queues
Fry’s knew that single queue multiple server had lower waiting time variance before everybody else in retail did. No surprise that John Fry funded the American Institute of Mathematics!