I know nowadays that doesn’t matter as much due to most DVD players or disc drives being region free, but I recall the time when I was younger in the late 90’s to early 2000’s most discs were region locked based on where you bought a copy (basically the same as buying a Japanese N64 cartridge versus an US one) meaning they won’t work when in another country.
For instance: I’ve purchased the first 2 home alone movies in Japan during my trip back then when they’re re-released on DVD (encoded as NTSC) while I come from a country where most discs by default are PAL so they didn’t work on my normal DVD player, having to purchase a multi region DVD player just to watch them. (This was before streaming sites).


Yeah but the main reason for all those copyright law differences comes down to “greed, money, and control” as the other replies explain.