The rugby player left behind his wife Paige and their children Kawariki and Arahia, whom the Chiefs dubbed as part of their whānau.
"With the outpouring of love from the rugby world and fans both nationally and internationally, our club wanted to set up a way we can all contribute to Sean's family during this difficult time.
"Once a Chief, always a Chief," they said.
Loved ones have left cards and flowers around a tree near where Wainui crashed.
Kiwi musician Stan Walker has also paid tribute to his fallen friend saying "we feel fully broken for you bro".
"Absolutely devastated my bro," Walker wrote on his Instagram page, which featured a photo of them with their wives.
"You are loved by so many...Biggest heart my bro....Sooo much aroha & prayers to your beautiful wife, kids & all your whanau...Moe mai ra e te rangatira."
Through his time with Taranaki, the Crusaders, Chiefs, Bay of Plenty and New Zealand Māori, Wainui had a profound impact on many teammates, including those within the All Blacks.
Tributes from players and teams have come from not only New Zealand, but also Australia. He was also mastermind behind the formation of the Crusaders' haka, Takina Te Kawa.
All Black Codie Taylor and his teammates touched down in Washington DC after a 35-hour journey to learn the news of Wainui's death.
"It really hits home. It shows how fragile life can be. You feel for his loved ones. It's hard, he's got kids," Taylor said as he shed tears.
The All Blacks held a team meeting to share stories about Wainui and the leadership group are discussing how to best honour him in Sunday's test against the US.
"It's pretty tough. I know there's a few boys in here really struggling as you'd expect. We touched on it this morning as a group and there'll be another opportunity to do that later.
"With a man with so much mana and respect it's so sad. There's a lot of shock."