This is one sentence I fail to understand. What do you mean by "possible"? When is it not possible?
Freeballing is not wearing underwear under your clothes. It is NOT like you are naked. When you dont feel like wearing underwear, then just dont wear it... I have been fulltime freeballer for quite sometime now, and it never bother anybody else. I freeball in my running shorts, in my jeans, in my dress pants (or some of you might call it suit pants). I even freeball to my medical checkup, and I have to change into those hospital gown (those that are open at the back), and that did not bother anybody as well.
As far as I know, it is ALWAYS "possible" to freeball. The decision is up to you.