They wanted Millsap, and it was clear that Bud wasn't going to trade him away.
Long term, there's the 2017 free agency ramifications to consider when you're taking into account, the long term luxury tax implications that is craftily waiting in the darkness to swoop the Raptors in. They have $76,749,940 committed to nine guaranteed contracts this offseason, but that doesn’t include Lowry, Ibaka, or Patterson’s upcoming free agency. Correct me if I'm wrong, maybe Saltlover can confirm.
Looking at the contract egiblity for Lowry on my phone, who is about to be 31, he is going to be able to obtain a tier three max contract of five years. Which will eclipse $207,060,498! He's going to most likely get somewhere close to that with absolutely no regard, considering how much he means to the Raptors. Pair that with Patterson or Ibaka netting a sizable deal, and the Raptors are already going to eclipse the $122 million luxury tax threshold.
Ibaka has a cap hold of $18,375,000, and is eligible for a tier two max salary which will render him around $30,600,000, or a max of $177,480,000 over 5 years. He's possibly not going to get anywhere near that number. But he will most likely end up around 22-25 million with raises based on performance. Toronto advantages over this gives him full qualify/bird rights, and being able to offer Ibaka the 5th year, but I question how this affects Jonas V, and Caroll, who are tying up $16,539,326, and $14,800,000 respectively. That's 31,339,326 alone in two contracts!
tl;dr
If they re-sign Ibaka anywhere near to 24-28 million, the Raptors will literally be banking on hoping that their starting five can win a championship, or a fire sale will start happening in one to two years.