The use of force to take money or other property from another is called Robbery; taxation is legal and thus not wrong.
Just because something is legal doesn't mean it's right. You recall that slavery was legal at one point, yes? Are you going to argue that slavery was right because it was legal?
I oppose the government taxing people in order to provide "free" contraception because I think it's wrong to use force to take other people's property.
Good point: "Just because something is legal doesn't make it right". The argument than becomes philosophical and ultimately ideological.
Now, the means to decide issues of morality have been argued for at least two thousand years, by minds greater than mine. So let's put the philosophical aside and concentrate on the ideological.
Let's also limit the argument to two sides: The bleeding heart liberal (BHL) and the callous conservative CC).
The BHL has empathy for the fetus and the expectant mother, and supports a women's right to choose but doesn't like the outcome. Thus s/he seeks a solution to this paradox. The BHL decides that to educate women and men (girls and boys) in an age appropriate health curriculum the methods to prevent pregnancy, and prevent sexuall transmitted disease, would reduce unwanted pregancies, abortions and the transmission of disease. Thus they support free contraceptives to men and women and to boys and girls who are sexually active.
The CC has empathy for the fetus and condemns the pregnant women for lacking self control. They will argue abortion is immoral and must be illegal and punished. They will force a pregnant women to have her child, support it for at least 18 years and not expect any aid from the government. I should had that the empathy the CC has for the fetus ends at the child's birth and for many CC's the issue of abortion as a wedge issue is more important than the fetus.
IMO there is no rational nor is there any honsest explanation for any person of faith to object to the BHL's POV.