Two things, the pocketbooks of the shop owner and the technology at the time of installation.
I have installed $3,000 cameras over 30 years and it is remarkable the technology that is available now compared to back then. In 1995 when I started a pan tilt zoom was a box camera inside another weather resistant box controlled by a matrix and isolation relays recorded on banks of VHS cassette tapes. The next gen were domes which were essentially stripped down box cameras manufactured inside a spherical housing controlled by relays, controlled by software recorded on a DVR. When I retired, Megapixel and HD cameras had been out for about 6 years and required terabytes of storage with NVR recording. Now you can store 8 of those cameras on a terabyte.
I was making bank going to old customers that had old cameras and selling them HD cameras with a DVR that didn't require rewiring with CAT5 like megapixels did. A 1 megapixel camera is outdated by SAMs Club $500 systems now.
