plastic

I am using the following water cooler as my chlorine dispenser, it works like a dream apart from the tap (button release) which has a metal spring and over time rusts and needs replacing. The hole in the cooler is 3/4" (19mm). I was wondering if anyone else has used plastic taps and am looking...

The attached picture is the bottom of my pool steps. The rubber has come loose - I was just going to clip it off at each end. Just curious if anyone knows what its there for. Decorative I hope.