I think posting over 100 pictures was the problem. It wasn't your event, so you posting so many pictures was ... not sure how to put this ... kind of over-the-top. I can see posting a few (a dozen maybe? Two dozen maybe?) of your best shots of your friends, but posting over 100? Too much. I can see the HC being bothered by that.
POD
If someone slogs through a 100 shots you uploaded few people will have the desire to then go through the professional album as well.
Leaving a few shots of you and your close friends would be fine, but more than 10 implies a certain amount of ownership of the event to me.
I go to events in NYC where sometimes, a dozen people will each upload several hundred photos each (the Jazz age lawn party is one). Some will even write blog posts covering the event. Sometimes the NY times style section even covers it. The idea that they are each "claiming ownership" of the event through this behavior is frankly preposterous. It's a visually and culturally interesting event, so people photograph it and write about it. End of story. The person who "owns" it is the organizer, Micheal Aranella, and he realizes that the photos are great publicity - whether they be good or bad, blurry or not.
In terms of weddings, they are fun, often pretty, and personally meaningful to people other than just the bride and groom. If that weren't the case the B&G wouldn't feel the need to invite anyone but themselves. The idea of inviting people to an event and then dictating their behavior is not good hosting, IMHO. It is also exactly what I am shying away from with my own wedding. No one is being told what color to wear, where they should sit, or when they should eat. I understand there are sometimes good reasons to do so but I don't like the idea of telling adults what to do at a party, I'd rather people have their own fun, and simply enable them to do so however they see fit.
I see this as a similar issue - telling someone they can't or shouldn't post these photos is a restriction that better have a much stronger justification than "it makes me feel sad that your photos aren't as pretty as our professional ones might be."
If you are having a private party and you want to have a photography policy regarding social media, you should think about that
before your event, not after, especially in this day and age.