You should inform the boss of how this came together. Make sure this guy is never in charge of buying any gifts, ever again. You request that he speak privately to the fellow about why this is inappropriate and makes him uncomfortable, and he does not wish to see such excess repeated. The boss should, in no uncertain terms make it clear that he would have much rather seen this money spent on the food drive, and if he was sucking up - that was the way to go.
Maybe it’s just me, but if I was the boss, this kind of excess would make me uncomfortable in the extreme. That’s not how gift giving is supposed to work. Not to mention the way it has skewed the other employee’s ‘gift to boss’ unfairly, possibly creating hard feeling among them as well.
Acknowledging the thought was very nice, doesn’t mean the boss can’t make his point.