Hmmm.. I'd say 99% of the time (in high school), if you're good enough to hit multiple home runs and you're able to get on the HR leaderboard, you have a very high average.. and probably one of the highest, if not the highest, average on the team. This is far different from college or the pros.. where EVERYBODY has the power to do it.. when you're able to hit 10+ HRs on the high school level, if your average is below .300 then it's probably a misprint.
Just sayin.. I believe it is an extremely important stat if you bring into consideration your teams opponents and field measurements (excellent points made above), but there are not many, if any, mendoza line home runs hitters at the high school level.