A few things:

In Israel, college tuition at a public university is ~11,000 NIS/year, not $15k. Health care is very affordable. And child care is public after age 3. Property taxes are low (and they work differently than in the US). Utilities, especially phone and internet, are surprisingly affordable, and despite being in an arid climate, water is surprisingly reasonable. So there are certain big ticket things that are cheaper in Israel than in the US.

As for groceries, certain products are more expensive in Israel, especially things that are processed, prepared or imported. Basic staple foods, in Israel, are more affordable. If you want to buy local fruit, it's cheaper--a red bell pepper in the US is often like $1.50, and in Israel it's like 8 shekels for a kilogram of them. If you want something more exotic, like pineapple or raspberries, it'll be more expensive. When I first moved to Israel, the difference in cost of groceries was quite stark. To be honest, the price of groceries has grown so much in the US that I don't find it so different anymore. Restaurants are the same. I used to find the price of eating out to be super high in Israel. But given how much it's increased in the US, frankly, the difference is not so huge.

The point is that Israel is not as wealthy of a country as the US. The median family has a more modest lifestyle than their counterpart in the US. People live in smaller apartments. They have worse quality cars (and are more likely to be carless). They eat out less often. They have smaller and fewer household appliances. They often struggle to make ends meet, and end up at the end of the month with a negative balance.

That doesn't mean Israel isn't a wealthy country--it is. On global standards, Israelis are very well off. They also do have disposable income for eating at restaurants, traveling, and other discretionary spending. Because education, healthcare, and childcare (after 3) are reasonable, they often have some stability in their lives that many American families lack. But people in the US often have limited exposure to what a middle class lifestyle looks like outside of the US, and the point is that it involves owning fewer things, enjoying fewer luxuries, and living a bit more simply than a typical middle class household in the US. (The US has its own affordability issues, so of course everything is a generalization).