Sure but the majority of MOUs don't get filed to the ASX as a...

Sure but the majority of MOUs don't get filed to the ASX as a price sensitive announcement. Wine Depot clearly have had numerous partnerships being negotiated behind closed doors (hence previous announcements) that haven't warranted this, so the point wasn't that they've just started discussions with eBay and suddenly over a weekend they've signed contracts, the suggestion was once it got to the point of negotiations (after what is likely many months) where it was clear the deal was going to cross the finish line, they issued announced to market as an MOU to prevent leaking prior to the formal announcement, and then subsequently made the formal announcement after paperwork was signed.

May well be something else, but this would seem like prudent behaviour to avoid issues with the ASX's reporting requirements if word got out and the price went nuts on something they were yet to announce to the market.