Does Honda sell oil in 55-gallon (or larger) drums ? I doubt that they do. Even then, it's unlikely that dealers would use it due to cost. Most off-the-shelf oils will more than satisfy the requirements that Honda specifies so one dealer could use Valvoline, another uses Mobil 1, another uses Pennzoil, and so on....
Even the oil that Honda puts in engines at the factory could change year by year. Just depends on who bids on supplying oil that meets their spec and has the best terms for Honda.