When / why did you give your kids squash? Or anything besides water/milk?

I was speaking to a group of parents the other day at a kid's party and they were all shocked, and a couple seemed to think it was outright mean, that my 2.5 year old had never had squash or milkshakes etc.

He's only ever had water or milk, our logic is we might as well make hay while the sun shines and keep him as healthy as we can for as long as we can, and it's not like he knows what he's missing out on. But on the other hand I feel a bit mean...

When / why did you start giving your kids squash?