30,000 Mile Spark Plug Changes

Since I’m bored while waiting for my Hornet to be built, I decided to see if there was any info about maintenance. After searching my local CDJR dealer servicing page, they have a factory required maintenance guide for the Hornet. (I compared this to three other dealers and the schedule is the same) It mentions having the spark plugs changed every 30k miles. That seems like an awful short interval for modern spark plugs. I did look up info on the Alfa engines and on the 2.0L it’s 60k miles and the 2.9L it’s 30k miles. Thoughts?