EventSub vs PubSub for subscription events

Hey everyone, I’ve been using the Twitch API EventSub for quite a while and it’s been working fine, however, I noticed that for the same event, we receive different payloads on EventSub and PubSub.

For example, the EventSub subscription payload looks like:

"event": {
        "user_id": "1234",
        "user_name": "cool_user",
        "broadcaster_user_id": "1337",
        "broadcaster_user_name": "cooler_user",
        "tier": "1000",
        "is_gift": false

On the other hand, the PubSub (WebSockets) payload has much more valuable info, such as cumulative_months, streak_months, context and sub_message:

"data": {
    "topic": "channel-subscribe-events-v1.44322889",
    "message": {
      "user_name": "tww2",
      "display_name": "TWW2",
      "channel_name": "mr_woodchuck",
      "user_id": "13405587",
      "channel_id": "89614178",
      "time": "2015-12-19T16:39:57-08:00",
      "sub_plan": "1000",
      "sub_plan_name": "Channel Subscription (mr_woodchuck)",
      "cumulative_months": 9,
      "streak_months": 3,
      "context": "resub",
      "is_gift": false,
      "sub_message": {
        "message": "A Twitch baby is born! KappaHD",
        "emotes": [
            "start": 23,
            "end": 7,
            "id": 2867

Is there any explanation behind why we don’t have the same amount of information on EventSub and are there plans to include the same info on EventSub?

According to the documentation, EventSub is going to be the main single source of truth for real time events.

TLDR: the subscriber topic doesn’t do what you think it does, it only fires data for a “brand new sub payment” so no resubs

User voices exist to extend:

And if the uservoices that I have listed is insufficent for your needs, take a gander at my quick sheet

And/or raise your own uservoice

That’s great! Voted on all of them!

I think I will need to use a mix of EventSub and PubSub for the time being. No problem at all, but it would be better to have a single source of truth for all events.