Four thousand years ago, when the Crossings Intercontinental Worldgating Facility on Rirhath B was in its initial stages of development, the populations of the Alterf star system were evacuated into near-Rirhait space secondary to their home star being irreparably damaged by a passing black hole. The four carbon-based species originally native to Alterf IV's giant moon Temalbar brought with them to their new homes an awesomely advanced sheaf of technologies that became the foundation of a cultural partnership with the Rirhait that has stood the test of millennia, and thrives to this day. Daily life in much of the modern Galaxy now depends on some of the devices and tech they brought with them - such as the Interconnect Project's worldgate management and deployment technology that makes it feasible to cluster worldgates together on demand without destroying the planet they're based on, and the far-famed SunTap limitless-energy capture system that satisfies the power demands of worldgate complexes in this galaxy and numerous others.
And that said... beings based on every sort and state of matter, and resident from this side of the Galaxy to the other, will swear up and down (if asked) that the very best thing to come of that ancient partnership is the concept of the multispecies shopping mall.