Depending on the system, it was probably loop survelance. Meaning a determined number of days on file then it is overwritten with new video. Usually 30 to 45 days. By the time JA told her whole story I imagine there is little video anywhere of anything.
In the case of major retailers, there are thousands of lawsuits brought against them each year -- the defense cost of which has to be built into the cost of goods sold, but I digress -- and judges often order digital data retention and archival in numerous cases, especially class-actions.
We know that LE had the California WMT and SLC, UT Tesoro receipts in their possession immediately upon executing the Yreka search warrant(s) upon JA's July 15, 2008 arrest, less than 45 days after the purchases -- and non-return.
They would not have known about the WMT return claim until long afterward, when she concocted her 1,176th or whichever number lie it actually was.
But no excuse on the Tesoro video, unless Tesoro just didn't have it.
I'd rather not say what WMT did or didn't have during the 2008 time period and prior.