I've never seen a table at a wedding that couldn't hold at least 12 people, usually they are ovals seating 10-14 (but even rounds can seat 12, and with 7 BMs chances are at least 2 will be flying solo). Caterers will push strongly to not have less then 8 at a table and even that they aren't thrilled with.
I'm not sure what you found insulting though I apologize for hurting feelings. I dislike head tables though and I can't apologize for that. I think they are impractical and I think its not kind to separate your closest friends from their SO's while allowing yourself and every other guest the option of sitting with theirs. And I do think its a bummer for the friend on the very end. YMMV.
Having worked the industry they *are* a logistical nightmare. There's a reason caterers started the sweetheart table trend (a lot of reception "traditions" are actually in place for practical reasons). 16 people at a head table would require 3 6-foot tables (and that would still be tight). That's a huge chunk of floor space with no place for servers to cut through, so they have to maneuver behind the guests, inching to the side with heavy trays in hand. Tables they can walk around are much easier. If the WP was smaller maybe it'd be a different story but we are talking about a huge group here. A head table with 2-3 attendants on each side is not comparable to 7 attendants each.
And maybe they did work socially in the past but the reality is, posed pictures do tend to run entire cocktail hour these days, or they are for 1-3 hours pre-ceremony, and the courses and speeches and special dances do take up much of the reception time, and bridesmaids often do spend 1-5 hours at salons (or the brides home, or hotel room, etc) either the morning of or the day before getting ready. Sure there are breaks in between courses & speeches, etc, but then its back to your table.
And the reality is people want to sit with their SO's. One can say its traditional for couples to not sit together at formal dinner parties, but if that's the tradition being followed then it should be across the board - the bride & groom should sit separately, their parents should be seated apart, their grandparents & relatives and all their other friends etc should then be seated at separate tables from their spouses & dates. Because at a traditional dinner party hosts didn't just separate their guests, they separated themselves too. Its fine to use any element of formal hosting but one should be consistent in its application.