You're missing the point, at least for a subset of reservation holders that waited in line. Nobody expected anything, of course. And then Elon tweeted that after he went down to the Century City location, he was blown away by the multi-hundred person lines at galleries across the continent (and world), and some in the wind and rain at that - iirc, they sensibly figured maybe 20-30 or even 50 people in line, but surely not 500 or 800. It was in that series of tweets that he said something extra would be headed to the line-waiters. Of course, with 115,000 or so of them, it would take awhile.
At that point, people recalled various kind gifts sent in the past for those who had waited years for their respective chariots - no line waiting, but still. And so there was a differentiation made between "usual and customary" gifts for those who made reservations (for example, to boost interest or to show appreciation just before next year's reveal) *and* the extra-special cool whatever that was headed to line-waiters.
As we sit today, some of the line waiters, and some of those who didn't wait in line but placed orders at galleries (showrooms) later in the day have received a smaller version of the artwork that was made available to the first M3 reveal event attendees. I eagerly await mine, which I am sure will be suitable for ironing and framing, and I plan to do both, should it arrive. And if it doesn't, despite being 7th in line that fateful morning, well, hey - it's the thought that counts, if not the execution. But make no mistake - since we were told to expect something, that's why many have been eagerly peering into their mailboxes lately like it's Christmas in July. And those who already have Model S/X who received something merely for making a reservation have asked if that will happen again as well. To your point, whether it's the most tasteful question in the world is debatable, but there is precedent.
Personally, I was beyond impressed that the CEO of multiple companies would take the time to go into the teeming hordes that morning and say thanks in the first place. Ever try to get from Beverly Hills/Bel Air to Century City on a weekday morning? Good luck with that. Traffic aside, how many CEOs of just one company would do that in today's day and age? Good stuff indeed.