Of course, to each his own, but it is so simple to add whatever you wish during pulling that injecting doesn't seem to be worth the bother--to me. Lilly's injection isn't one I'd see myself using were I a butt injection fan as the sugar content is over-the-top for my taste. It does follow the 'meat candy' dynamic so popular at comps--but that just ain't my preferred profile.
I can see injections for thick meats (butts, hams, beef roasts) that will be served sliced. I usually just sauce or have have sauce available but I can see the use of flavor injections here and on occasion use them, especially for meats that will likely be served unsauced (like for 'cold cut' platters) or where sauce would otherwise get in the way.
Still, it's one of those personal preference things, injections are not hard to make or vary, and can be worth experimenting with.