Why would anyone buy a Bugatti, when you just can have a regular VW? Why go into space when you can stay on earth…? Maybe because the space is there. Maybe because you like the challenge, and see how far you can take it.
If you got the money and muscle - why not.
It's a matter of 'choice'.
I could reflect on this topic from many perspectives, but I'll limit myself.
However, one may wonder about the intrinsic connection with 'the gear' - whether it's a Veyron or a 3 million high end setup -
and what it's supposed to provide in terms of the experience.
Apart from top speed (that you can hardly experience these days, not even on the Autobahn), a Veyron isn't necessarily 'better' than a Aston Martin Vantage, or a Lamborghini.
The Veyron is one of the brainchilds of Ferdinand Piech, just like the VW Phaeton, of which the W12 version, I can say from experience, was actually astonishingly good - also compared to the competition. Still, the original Audi A8, with the improved 3.7 V8 in the non-quattro version, was a much better car for high speeds and in terms of overall ride/handling.
If you're willing to spend:
$20,000 to $30,000 for a basic service, $40,000 for a yearly fluid change, around $60,000 for a set of new tyres and $75,000 for a set of wheels that need to be replaced every 16.000km, go ahead.
My brother knows someone who has installed several pairs of Living Voice Vox Olympian + Vox Elysian for cinema use in a superyacht, the acoustic conditions of which limit the performance to Altec VOTT-level.
Above a certain level, (exorbitant) material wealth rarely adds anything substantial to the 'experience'. On the contrary, because if you cannot intrinsically connect with the technology, or at least its performance (on a deeper level of understanding), emptiness will eventually overtake you.