HS HR's are hugely effected by field layout. Our park is big and prevailing winds blow left to right. We rarely see more than three a year by both teams combined. There are a few parks in our area with shorter fences and different wind conditions and the same teams will combine for 10-15 per year. There are a few small schools in the region with no fences and the result is that very average players pile up some HR's.
BTW, a college summer team also played at our park for a few years recently. They played later in the eve when winds die down. Combine that with the older, better, stronger players and it was fun to see quite different results.