Keep in mind who pays for the replacements - U.S. Citizens to the tune of $317.9 billion over the last 70 years [1].
1. Israel's sugar daddy will give (as in gift) them all the munitions they need. They'll never come close to running out.
2. This is the country that's been crying wolf over Iran being months away from having the bomb for something like twenty years now, while having up to several hundred nukes of their own. Why should we believe them when they're crying wolf about running out of munitions?
What exactly are you buying with that money, to know it's cheap?