CPT ArkAngel the figure is so much smaller than the 1% you quote I really must give you a more accurate figure.
A the core of a dense globular cluster can contain about 100 - 1000 stars per cubic parsec say about 30 cubic light years that is a box abut 3 light years across. This is compared with the one or less that is in our region of the galaxy.
Giving each star a cubic space about the size of the earth's orbit. Thus is plenty of space to allow them to pass each other without any significant effects.
This box is around 20 light minutes across 3 boxes in the side of one light hour 24times for a day 365 for a year say about 25,000 so there are 25,000x25,000x25,000 = 15,625,000,000,000 such boxes up to 1000 of which contain one star. so the odds that any box contains a star is 1 in 15x10^9 and stars passing within these vast number of boxes are very unlikely to collide.
The sun is about 1.5 million Km across and the earth is 150 million Km from the sun so it represents about 1% of the length if the box to there are 100x100x100 = 1,000,000 boxes the size of the sun inside the earth's orbit.
So if a star passes through a box the size of the earth's orbit the odds are around ten thousand to one against a collision.
Considering that typical velocities might be around 100km per second it takes one star about 150,000,000/100 seconds
this is around ten weeks or 1/5 of a year
Putting this all together there is a 1 in 10,000 chance of a collision 15/5 x 10^9 years that is one direct collision every thirty trillion years agreed there are a lot of globular clusters in the universe but collisions are vastly rarer than supernovae