Man does indeed frequently use available space for aircraft parking (or even car parking
)
Aircraft have been parked on TWY Bravo (B5 next to stand 12), Engine test bay, TWY Alpha near the ETB, on some of the recently completed new sections not yet in use etc, etc.
Then you have TWYs Quebec and NB which are routinely dual purpose TWYs or stands.
Unsurprisingly the decision/choice considers how long, need to access aircraft safely and ATC views etc, etc.
Like all these decisions the final choice is taken after stakeholders are consulted and safety impact assessed.