This is one of those things that just about all of the solutions mentioned are totally safe althogh they may have some tecnincal violation. It would be unfortunate to not use the pipe and create a lot of extra work for no good reason.
At a forum I visit (non pro) their favorite suggestion for shop & garage feeders is MHF.I would pull 2-2-4-6 mobile home feeder. You won't find a cheaper cable than this. It can be direct buried, and even better sleeved through the pipe. You could use 1-1/4" or 1-1/2" PVC from the ground up. I wouldn't use EMT for this.