WTF? The distance is between the caliper and the wheel. 7mm. No issues. No problems. Just told everyone what it was. I really don't think a "rock" or anything else for that matter will "find" its way between the two. Just look at where the caliper is mounted (height wise). The space is on the outside edge of the caliper and the spokes of the wheel (inside edge). My car is not an off-roader.
WOW!!