Everywhere I've lived non-scheduled bus routes run like every 5-10 mins anyway.
Also, just walk for a bit? Or instead of doing a grocery trip pick some stuff up on the way home every day, one of the advantages of cities is usually, bus or walk, there's a grocery store on your commute home. Like you don't need to isolate every bit of your life.
I don't know anyone who lives in a city who can't just walk to grocery store
Careful, there's enough fools who know about urban "food deserts" caused by other things totally unrelated to population density that assume it's some phenomena that only occurs because of density.
Fuck there's even bicycles made to help you carry several bags back as well (I've also seen people with those sweet foldup carts too which are nice)