Dal Santo crossed to the Kangaroos as a free agent last week, after 12 years and 260 games with St Kilda.
Speaking at Arden Street for the first time on Tuesday, the 29-year-old expressed empathy for fans losing their favourite players to rival clubs, but said it was a modern reality.
"In my opinion, [players will stay at one club for their whole career] less and less," Dal Santo said.
"If you play eight or 10 years-plus, I think it will become more and more difficult.
"But that's the environment."
Dal Santo's move to North Melbourne came a year after another Saints favourite, Brendon Goddard, crossed to Essendon as a free agent.
The three-time All Australian said he had never thought he would leave St Kilda, but had come to realise it was the best move for both he and the club.
He said, while the speculation about his future had been difficult to deal with during the season and in the lead-up to his signing by the Kangaroos, it would be "hypocritical" to complain.
"The AFLPA, with the support of the players, pushed for free agency, so it's disrespectful now to say it's not working for us," Dal Santo said.
"As players, we were so focused on having an option, and a choice of where you want to play your football, and I think that was really important, and I still do.
"I just think that at the moment, free agency is still new and fresh, and it received a lot of attention last year, particularly with Goddard leaving, and I saw first-hand the speculation and media pressure that it puts on a person.
"I think it will become a bit more relaxed in years to come.
"I don't know if I can see it necessarily becoming like rugby and American sports with guys leaving clubs mid-year, but I just see it being a little bit more open and accessible and understanding.
"I think it's still a great cause, and I still believe in it."
For fans upset at losing players, Dal Santo provided a reminder that the system would work both ways.
"I can understand the fans' and the public's questioning of it, because when it doesn't work out in your favour it can hurt a little bit," he said.
"But in saying that, you'd like to think that every club will get an opportunity to get a free agent, and it will work in their favour at some stage."
