Walkers are also really bad for their foot development and can lead to baby rolling their ankles as they walk.

Cot Bumpers (from my understanding) are more for if baby is playing in the cot and should be removed when bub goes to sleep.

As to why these products are available i really cant help with that

Also the Jolly Jumpers can be dangerous is you have more than one child as the older child/ren can push the bub into a wall

Does make you wonder