I think it's very important to note that the act of making a Choice / Avoidance decision is itself a pleasure, because that immediate gratification conditions the brain towards making Choices / Avoidances in the first place.
Here's a first effort at a response:
On a very basic level I'd start off observing that it seems to me that Epicurus is saying that simply being alive and not in pain is pleasurable, so the act of choosing / avoiding would also be classified as pleasurable unless there's something specifically painful about the situation.
Now it is necessary at times to think about this to realize it, because some choices may not involve immediate mental or physical stimulation, and the standard philosophical position other than Epicurus was/is that there is a neutral state where you are experiencing neither pleasure nor pain.
So I do think it's correct to say that in general being alive and making a choice / avoidance is pleasurable, and it's important to think that way. But to suggest to someone that exercising choice is going to produce immediate pleasurable "stimulation" in the sense of eating candy isn't likely to be the way to look at it.
So I see this as an occasion to be very clear about what is meant by pleasure.