From my experience most online sellers sell at a price that is just slightly over (within $10) of the wholesale cost from distributors. I'm not sure how they could discount it much and still make anything.

They sell lots of balls each day, banking on volume, and I don't think a 6 ball order would hardly be a blip on their radar.

For a stand alone shop selling a bunch of new balls in box just above wholesale doesn't make them anything and may cost them future sales of the ball. It would only make some sense if they would it a volume break price point from their distributor and get some assurance the balls would be drilled in house at their normal drilling fees.

I appreciate this viewpoint. and if we snag a discount somewhere, and it's only going to save us maybe $10-15 a ball, it won't really be worth the headache, and unlike what itsallaboutme thinks, i'll be more than happy to use my normal driller to order the ball through.  There IS a reason I still use the shop I now live about 3 hours away from.  He is good, and treats us well.  He also understands business, and customers saving money.   He himself sends people online for shoes and bags, cause he just can't compete with those prices, still some people order those through him anyway.  He's going to get paid to drill all 6 of these anyways.

I came into this topic skeptical if there even was a place to get a mass discount, but was curious if it was available at a steep enough discount that it'd be worth it.

I doubt you will see much if any discount on the ball price
But you should see a discount on drilling if you are all going to the same place.
I would try a cliff barnes pro shop and see what they can do for you.
my local one is operated by Bill Monce.
his shop # is 1-414-305-4985

I'm also in the camp that bulk buying for the consumer wont typically yield much of a discount. Pro shop businesses are very labor intensive kinds of operations. Many people will buy a ball and are reluctant to pay for the labor. Many proshops don't make a ton of money over cost of merchandise so to spend time to drill 6-8-10 balls for someone and not charge for that labor is only hurting himself, unless business is really bad then it doesn't make sense to give the labor away for free. How much is your hourly wage worth to you and how does it feel after a 25% discount