The explanation might be simpler than you're suggesting. When a registered trademark is used by someone other than the person holding the trademark, it's often allowed if the use is in an unrelated domain -- in this case, computer software, not candy. Because this doesn't confuse the public or hurt the originator's business, often there's no complaint.
But the fact that Google has been favoring food names doesn't change the basic idea, that those uses won't confuse the public who are in the market for the other kind of ice cream sandwich.
