If every woman who was sexually harrassed just quit, the workplace environment for women would still be like the '50s. Individuals have to make a stand for better treatment for all.
I'm not in the US but I sincerely doubt that harassment is that common.
Harassment is very common in the US and even more common in Europe.
If 1% of guys are scumbags, and 5 days a year they really act like it, and you play that out for 10 years.. most women could be harrassed at some point or other even though 99% of guys are innocent.