Physical Danger
The average speed of a soccer ball when kicked by a professional is 60 miles per hour. Which is pretty cool that you can make something move that fast with just your legs; the other edge to that sword includes that speedy ball and your face. Quick way to rearrange your bone structure.
And that's assuming you're playing against people who wish you well and who aren't intentionally pelting you with soccer balls. We hate to break it to you, but soccer is uber competitive and some soccer players aren't all that nice. Just ask these hair-iffic soccer players. Now ladies, go invest in a trendy pixie cut. And lads, keep that hair short. Protect yourselves.