Is my vet ripping me off?

My vet sends out notices for periodic checkups for the kittens. It's a nice reminder. But I noticed they are calling for a second stool examination on the latest card. They just got a stool examination at the last visit, and they were worm-free.

I've been feeding them kitten food, wet and dry, and nothing else. Why would I need another stool examination? Can kittens just develop worms out of nowhere? My kittens aren't allowed outside either.

What should I think? Stool examinations at my vet are expensive, 40 bucks a pop.

The two kitties, now 20 weeks and 13 weeks respectively, sure do use the litter box a lot. They fill the littermaid waste recepticle every four or five days.

So I guess, what is normal here?
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You are probably getting a standard form that most vets send out with all the reminders on them. A worm infestation can occur overnight, and your vet has no way of knowing if you have been keeping de-flea treatments up on your cats so this is just a reminder. A fecal at my office only runs $15.00 but I live in a rural area where the vets take into consideration the farming aspect of life and money issues. One vet I know of will not even examine a cat unless it has all the shots up to date and he does a complete exam every time you bring the animal in, from the normal taking vitals to looking for lice, checking the ears, the teeth, etc. He just built a huge new facility so his business must be good.

That "Bring a Fecal Sample" sticker is also on my Vets reminder cards - just routine. He does not ask for it when I come in for the booster shots unless he sees a good reason upon the standard once over or due to something I might mention during the visit.