I don't see why not... The only issue here is Xenforo's coding of the website. I think if it was something to do with the chat box or search boxes, etc., then they would add it to ALL Xenforo websites. Unlike the medals, which can be made forum/server specific. TL;DR If they can, yes.
Since tables are such a popular/common thing, I was surprised they didn't have it, so I kinda figured it was disabled. If Xenforo doesn't support it, then I will be amazed. Thanks for the positive feedback.
I think (But I might be wrong) Xenforo would have to change amd add this themselves. I don't think that ECC staff can do this themselves.
When you're writing a post, do you see the little boxes above your text? There's options to make it bold, italic, underlined, but there's no option to make a table. I'm assuming you know what a table is. What I'm suggesting is that the new box would look something like this. You select a size, then a table appears with the amount of colums/rows you selected. Hope this clears it up!