A real question would be why the general population on this site tends to fabricate double standards to feel sorry for themselves and shit on feminism.
The problem with feminism which concerns the OP the most, is that they object to objectification of women and thus at one point may interrupt his enjoyment of his hentai collection. ...........:|
To answer you question:
Mostly due to lack of understanding and education about the underlying issues which constitute feminism and why it's important. Some are outright misogynists. Then there are those misogynists who try to benefit from this ignorance and distort the definition for their personal benefit..
Often it's combines with insecurity, ego, not wanting to share the same platform they have had all to themselves for a long time, a sense of loss of control( property rights, absolute rights within family etc). The idea that woman can walk out without or at least considerable less negative repercussions yada yada...
Some also confuse misandry with feminism as misandrist use feminism to justify their behaviour.
At NB- It's kind of funny when people scream racism is alive and needs tackling and then turn around call feminism all wrong when it's still claiming so many lives around the world.
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OT:
I don't think women get excused- In fact I have seen guys making jokes on them claiming that they are just afraid of the competition they have for attention of remaining men. So a lot of their arguments ( Not commenting on righteousness of the issue) get even less attention in such debates.
So .....I guess it's just a matter of perspective.