It's about 40% offered proactively, 40% passively there at boarding (my preferred) and about 20% pre-placed at the seat (particularly in F and even more particularly on UA*G7)

Speaking of G7 they continue to blow the rest of UA out of the water with snack service, e.g. yesterday on DCA-EWR they had the cheese platter "entree" along with a second "snack" which seems excessive for a short flight but very elevated and appreciated...similar os typical for RIC-IAD and vv... Compare that to the other UAX operators and mainline where just the snack basket is so hot or miss I don't count on it, even on longer flights
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