Thanks to some new details provided by Toriyama, it seems the Saiyans were trying to put one over on Freeza too.
Well OK, and this one too. It's weird to see him call it "Cold's army". pic.twitter.com/bsQAxdhtqT— Todd Blankenship (@Herms98) December 1, 2017
In a Q&A printed in the January 2018 of Saikyo Jump, series creator Akira Toriyama dished a bit over the Saiyans' relationship with Freeza when asked whether or not they had superior technology stating, "While their science isn't all that advanced, I think they are ahead of Earth when it comes to spaceships and combat stuff, since they've been attacking other planets since way back when."
And when it comes to Freeza, "[A]fterwards they joined the army of Freeza's father Cold, which had vastly more advanced science than they did. Cold's army provided them with virtually all of their weapons, armor, machines, etc."
As many fans have guessed, Freeza's army provided the Saiyans with their Scouters, armor, and space pods. So the Saiyans may have eventually grown comfortable as part of Freeza's army, they initially only joined the army in order to take advantage of their technology and improve their conquering skills.
The Saiyans were still a formidable race, however, as Toriyama did confirm that the Saibamen weren't a scientific creation from the Saiyans or Freeza's tech but a conquered race the Saiyans has stumbled on and exerted control over.
Stating that "the Saibamen are one of the Saiyan's classic weapons. But the Saiyans didn't invent them; rather, they are a life-form discovered on a certain planet...they can fight on their own, but they are also an extremely rare and valuable item since harvesting their bulbs is difficult, so not everyone gets to use them. Plus they're so wild they might attack you, which means only a select few warriors are capable of handling them."
This same interview also went into detail about other surprising Saiyan quirks like why they can and do eat as much as they do, and why familial bonds don't seem as important to them. These extra tidbits flesh out the Saiyans outside of battle, something the Dragon Ball franchise doesn't always have the luxury to do.
Dragon Ball Super's "Universal Survival" arc is part of the recent simulcast agreement that sites like Crunchyroll and Funimation have scored. Dragon Ball Super airs on Crunchyroll Saturday evenings at 7:15 p.m. CST. Adult Swim airs the English dub during its Toonami block Saturday evenings at 9:30 p.m, and is now available to stream on FunimationNOW and Amazon Video.