I've been playing the game quite a bit and the energy drinks have helped me to progress multiple characters at the same time.Y'all might want to actually play through the game a bit before you start making "QoL" recommendations to a Dev . . .
As you improve your power, you'll gain the ability to initiate a third event before you'll need either an energy boost or sleep; and Sarah will eventually provide free espresso when she works at the Coffee Shop - you can slam 3 coffee in a single visit without triggering time passage.
Since your opportunities to use your power are largely scripted, there's no need to stockpile energy boosters - and if you are attempting to completely corrupt either Sophia or Chloe in one go, you'll miss content related to their daily activities.
I'm not trying to chain events for the same girl on the same day.
And given that farming xp with Ava or by studying in the school library uses one unit of power each, those energy drinks helped with that too.
I haven't progressed much with Sarah yet (just started the coffee shop job) because she is less appealing to me than most other characters. It's nice that you can get espressos from her but alternate ways to get multiple energy items would still be a good qol.
And if you are wondering how I'm making money, in the very beginning of the game as soon as I got 25 bucks or something like that, I went to play some blackjack and made 100k in about 10min.