Originally Posted by Yosemite
De-worming should only be done if tests have proven that your cat has worms of some sort.
Or unless you see unmistakable physical evidence yourself.
As I said, Revolution is enough. Give your pocketbook and your cats a bit of a break. Depending on how your home is set up, if you dust your pant legs off or stomp your feet before coming in, or if you have a true winter that gets below freezing - often you don't need to use anything during the winter months.
Also, tapes are carried by fleas - round and hookworms are something a cat would pick up from being outside themselves (contact with soil/infected feces) or eating parasitized prey.
A cat becoming tolerate to the flea treatments or wormer is not your only worry. Some cats can actually become sensitive to them. All vets will suggest you buy treatments from them, that's how they make money.
I'm going to guess that the highnote, like many others, is just very grossed out about the thought of parasites and a bit protective because of it - or even possibly worried about catching them from the cats (there's been threads about it before).
My suggestion to highnote, you don't have to believe what you've been told by several cat owners. But it wouldn't hurt to do some research and maybe reach your own conclusions from that.