Harmony (webcomic)/WMG

All the mega-companies merged into Buy 'N' Large
After the White Ship left without their representatives and ads, all the mega-companies pooled together to accomplish the until then impossible interstellar travel. They eventually merged together into one big mega-mega-company named Buy 'N' Large that set about making the cruise ships --including the Axiom--as escapes for the people and creating the Wall-E units to clean up the Crapsack World. What happened after that? Well, I think the movie covers that for me...

One of the mega-companies is Santa Claus
The company builds a crapload of toys. Then their many employees take time machines back to practically every past Christmas Eve to give to all the good kids of the untainted past. Unfortunately, that generated the greed that eventually led to the Earth getting sucked dry.