Studies have found it would be far more cost effective, and save more lives, to increase the female vaccination rate rather than giving it to men. The current national vaccination rate among teenagers for most recommended childhood vaccines is 80-90%+. For HPV, for girls, it is well under 50% nationally, I looked it up, it stands at 37.6% (2013).
The HPV vaccine is not cheap. In fact I am pretty sure it is the most expensive routine childhood vaccination in the US. For the three doses it costs ~$500 in the US and that is just for the vaccine, you need to pay more on top of that for the doctor and nurse to administer it. From Google the average doctor visit in the US costs $89 so that is around $750 (three visits) to get the vaccine. That's very very expensive.
How many men are in the target group of 12-26 year olds? I'm going to guesstimate 30 million. That gives us a total cost of $22.5 billion to vaccinate all men in the target age range, with an ongoing yearly cost of $1.5 billion (based on ~2m men being born each year in the United States).
That's a lot of money to prevent a few rare cancers in men and provide herd immunity for a virus that is usually harmless - and again, if that much money is just floating around you would be better off spending it vaccinating more women as they are nowhere near 100% coverfage.
If the vaccine was cheap, I'd say sure, give it to everyone. But it's not, and you need to look at the cost side of the equation. Most countries simply don't think the extremely high cost of giving it to men is worth the relatively minor benefits.
Sources:
Decisions to recommend the vaccine for boys and/or men depend on the epidemiology of HPV-related diseases in a specific country, the cost-effectiveness, and the affordability of the vaccine. Economic models have shown that including adolescent males and men in the current HPV vaccination programmes is unlikely to be cost-effective as the value HPV vaccination provides in this population is low for the money it costs.
Boys are routinely vaccinated against HPV in some countries, such as Australia and the US. In the EU, only Austria recommends both boys and girls to be vaccinated, although at their own expense.
http://eiw.euro.who.int/profiles/blogs/hpv-vaccination-in-eu-countries-review-of-new-evidence
Given currently available information, including boys in an HPV vaccination programme generally exceeds conventional thresholds of good value for money, even under favourable conditions of vaccine protection and health benefits.
http://www.bmj.com/content/339/bmj.b3884.long
HPV vaccination of 12-year-old males might potentially be cost-effective, particularly if female HPV vaccination coverage is low and if all potential health benefits of HPV vaccination are included in the analysis. However, increasing female coverage could be a more efficient strategy than male vaccination for reducing the overall health burden of HPV in the population.
http://www.sciencedirect.com/science/article/pii/S0264410X11011467
But just go ahead and downvote me, I'm aware that Reddit has an absolute hard on for vaccinating absolutely everyone for absolutely everything with absolutely no regard to whether it is actually medically necessary or makes sense from a cost-benefit standpoint.