Not trying to say I understand these people, but the whole episode brought up Szechuan sauce from the beginning to the end. It wasn't really a gag if the whole episode pretty had a Szechuan sauce C plot, from him talking about it in the beginning, to going to McDonald's to get the sauce, to the alien guy eating the sauce and commenting on how good it was while Rick's wife died, to his rant at the end about the sauce being his arc and him not giving up until he gets the sauce again.
The 3DS/Nintendo call out was a gag, Szechuan sauce was like a special guest in the season opener.
Fans still are acting like entitled asses about the sauce though. Glad McDonald's drummed up hype and helped a few people throw away a few hundred dollars for some nugget sauce that we'll all be able to get in a few months. Probably still won't like it, thought it was crap the first time it was out, but I might remember and pick some up this winter.