It looks like you might be being downvoted, but this is super valid. Herpes and HPV are extremely common among those who are sexually active. It's virtually impossible to avoid either and have lots of sex with multiple partners.

But obviously one can have lots of sex with a single monogamous partner though without any new risk of STDs.

One of the two you mentioned has a vaccine that many get as a teen now and the other is an occasional rash for most carriers.

Obviously everyone should consider the risks associated with having sex with lots of partners but those two particular STD's are pretty low on that list of risks.

True. I only mentioned then because they're virtually omnipresent and are transmitted from skin to skin contact where a condom offers only partial protection at best.

Many other STDs need some sort of fluid transmission which is at least easier to avoid.

Also, the vaccine only protects from a few of the hundreds(?) of strains of HPV. It protects from those varieties that are most likely to cause cervical cancer, but generally not those that cause genital warts.