TPMS Rebuild Kit

I need to replace the OEM tires on my 2007 Camry (22,000) miles and Discount Tire is pushing $10 each TPMS Rebuild Kits. They insist that without the rebuild kit that the tires will be at risk of leaking.

What is the general consensus on the need for replacement "parts" in this situation?

I'd be curious to ask what is in their rebuild kit that costs so much. In general, when any tire is replaced after normal wear, the valve stem is replaced, too. Otherwise, the rubber o-ring that seals it against the rim can get old and brittle, causing an air leak like they suggest.

Now, with TPMS, you can't just toss the old stem because it is attached to the pressure transponder. But you can replace that seal and the valve core, which by my guessing would cost about $5. If they also add the washers and nuts, maybe $10 is reasonable cost for the convenience.