We thought it'd be really cool and immersive and stuff if you could control the game using only your mouse. We accounted for people without a pressable scroll wheel but didn't think anyone would partake in a game jam using only a trackpad so that's on us.
As for continued work on the project I don't think any of us are really interested in that so it is very unlikely to happen. Maybe some day when I'm bored I'll add in keyboard support but it's not really on my list of priorities as there's a lot of work coming up for me.