+1 the shame is that we are in a disposable, throw away society.

+1 keep the old top in tact, its part of the character of the bench. If you must have a smooth top, cut a sheet of plywood or OSB to fit over it, but I would leave it as is.

My neighborhood is full of lazy folks that throw out all kinds of reusable stuff. Why they are too lazy to drop it off at Goodwill, which is less than a mile away, escapes me. We talk about being green, then we fill up the landfill with totally usable, recyclable stuff. I picked up a bottom end bike yesterday, that I will drop off at the local Goodwill. If you can't use it yourself, pass it on!!