"all expenses paid" means...

alll expenses related to business travelling, such as flights, hotel, car rental, gas, parking, toll fees, foods/drinks, tips, laundry (if you need to stay longer than one week without going home), phone, etc. Normally there is a limitation on food, anywhere $40 upto $64 per day. Without specification, use common sense.

Special Notes: Drink - if drinks like "Mageritta" are part of meal (like dinner), you'll have one receipt, all should be paid, however, if you walk into a bar and drink a lot there, you may not ask for reimbursement for that.

Each company has their own regulations per location and other conditions. However, you can take this as a reference: (general guideline on travel expenses)
www.gsa.gov/mie

Good luck.