Adventurers are made of pretty stern stuff. Such stern stuff, actually, that besides sleeping in armor and getting in a full eight hours of Z's while being ready to wake up and take their shift at any moment . . . they get up and go adventuring without coffee.
Breakfast? Cold rations.
Lunch? Cold rations.
Dinner? Cold rations.
And not a spot of tea or a cup of joe to get going in the morning.
Let's fix that.
Delver's Breakfast Tea - If drunk hot, the character is at +1 to HT rolls to resist weather-related effects and +1 to Per rolls for 1d-3 (min. 1) hours. Gives a +1 to reaction rolls from anyone given some tea. Preparing tea properly takes 15 minutes and requires a hot fire. $1/packet or cup's worth, 10 packets/1 oz. (A nice tin holds 100 packets and weighs 1 pound full, and costs $110)
Cartman (as Peter Panda): "Wow, Eric, you are the coolest guy in the world. This is tremendous tea!
Cartman: "Why thank you, Peter Panda, It's a distinctive Earl Grey."
- South Park ep 113
Knight's Roast Morning Coffee - Like Delver's Breakfast Tea, If drunk hot, the character is at +1 to HT rolls to resist weather-related effects and +1 to Will and Per rolls for 1d-3 (min. 1) hours. Aroma while brewing gives +1 to chances of a wandering monster encounter, and preparing coffee properly takes 15 minutes and requires a hot fire. $2/cup's worth, 5 cups/1 oz. (A nice tin holds 50 cup's worth and weighs 1 pound full, and costs $110.)
So, Tea is friendly and makes you sharper. Coffee draws in wandering monsters who want some coffee, but it also makes you a little sharper than tea.
A harsher reality would be to start everyone down 1d6-3 FP (min. -1) if they don't get some coffee. Or better yet, to stop players from just saying, "We rest an extra 30 minutes and we're good" give them a -1 to all rolls for 1d-3 hours (min. 1) if they don't start the day with coffee or tea.
I prefer the bonus approach.
What about Swords & Wizardry?
Change the cost to gold pieces (this is good tea or coffee). Change the bonuses from Tea to +1 to Saving Throws or Int or Wis stat checks for one hour. For coffee, the same, but add +1 to any stat check or +2 to Saving Throws for one hour. Shift the wandering monster die one smaller (So 1 in 12 becomes 1 in 10, 1 in 6 becomes 1 in 4, and 1 in 4 becomes a coin flip!)
Now start adventuring with some nice coffee.