People do things for shits and giggles all the time. SpaceX literally launched a model Tesla for absolutely no reason other than advertising both themselves and their sister company.

Doubly so if they can now become “the furthest man made object”. That’s massive free marketing.

It may also be exponentially easier to do so in the future, lowering the expenditure needed to make it happen.

It might not be reasonable right now, but, once again, the bar was set at always. That is an exceptionally high bar with very little reasoning behind it.