From photos of DCC taken at social events, I haven't seen that many with Victoria. I would guess that she may be viewed as someone who might talk to TK or Kelli about them and that when with her socially they have to be guarded in what they say and do. Much easier not to invite her, it doesn't mean they hate her, but they can relax more when not in her company.
Until exposed to diverse groups of people and gaining more experience in "the real world", Victoria will react and behave as she has been allowed to in her life up to this point. If you are allowed to get away with things and there are few to no admonishments, chances are your behaviors will continue until finally corrected (usually by a new peer group). Kelli giving her perks before she had earned them was a huge disservice to Victoria and IMO has made it harder for VK to grow up, face consequences, and make genuine friends.
On another note, I liked Maddie's dress, maybe simply because it was so colorful. Everything here in winter is so dull and drab. It gave me hope for warmer weather in a few months!