I usually won't buy coffee when I'm out and about. 1st reason is that of all the places I've tried straight espresso, I've yet to find any shop that compares to what I roast/extract at home. 2nd reason is the cost as having owned/operated a full blown mobile setup years ago I know what things cost. Yes I'm aware that cost involves equipment, electricity, labor, insurance, COGs, etc. That double shot in my area costs anywhere from $1.75-2.50. What I home/roast and extract costs me an average of .30 per double and the taste/texture is outstanding for me. If I want/need caffeine away from home I simply look for a can of Monster as it's not too costly for what you get and the taste/energy is very predictable/consistent.