On Saturday there's usually not as many people home watching Television so they put the worst shows on and show commercials mostly.
They figure on Saturday and even Sunday that mostly older people are at home watching TV and so they want to show commercials and other crappy shows.
Some people on Saturday and Sunday while off work are outside doing other things and enjoying the weekend and are not usually in the house watching TV.
It's always been like that with crappy shows on Saturday.
I don't watch much TV anymore because I watch Youtube mostly.
However if you only have antenna TV as free over the air TV then I would recommend getting Dish Network TV or other paid TV service because there's much more better shows on them on Saturday and Sunday than there is on antenna TV.