With regards to buying your way into ITU events, sure you can. At least, Canadians can. Even if you didn't even race at a qualifying event (never mind actually qualifying at one), you can put your name on a list, forget if its charity or whatever, and they will let you on the team. I believe you have to pay twice the entry fee or something like that, plus the usual cost of the team kit, etc.
Here, check out 'stage 3' of the qualifying process.... http://www.triathloncanada.com/.../itu_ag_team/worlds/