Never had a problem with it:
1) Look where they are. Even little kids would have to be on their hands and knees or bending down to get to them. Most of the time, they are looking at your face or your gun.
2) The pockets on most of the suits tend to be just bigger than the respective tools, so they tend to be snug enough that you would feel someone tugging down there
3) If things are so crazy or you are so surrounded that you'd have a difficult time seeing or monitoring something like that, you should have a wrangler or handler nearby anyway
4) There's so much going on with the costume, that the shin tools are generally the last thing anyone notices -- especially since only the tops peek out.