They’re different enough by size and their habitat that we don’t encounter them as primates so logically we don’t have any reason to have an aversion instinct. Regular insects can be poisonous or parasites but these don’t really look like insects.

You can do it yourself but generally not in a group like that for most people.

Actual bricks are rough and crumble a little bit occasionally, you’d probably want to coat that in some epoxy.

There are certain unique experiences you don’t get later. There are a few places that have field trips in college, but for most people that is only during regular primary school.