I'm curious why ITA doesn't actually make it possible to BUY the tickets. It seems silly to walk people through the entire process, provide them with so much in

I'm curious why ITA doesn't actually make it possible to BUY the tickets. It seems silly to walk people through the entire process, provide them with so much information about available flights and prices and then say... go and find someone else to sell this to you. Why not just partner with a travel agency and make life easier for people?