I'm fairly lazy so rather than make one or two cups of coffee a day, I prefer to make a one-week batch of cold brew at a time. (It's also a pain to manually grind that much coffee at once.) Cold brew is a lot more forgiving about "grind freshness."

I'm considering buying a grinder, but it'll probably be $100-200, and I'm not sure if that's worth the price when the coffee shop will do it for me.