I am a self emplyed tax consultant working in association with some advocates, my office is small without a seperate canteen. But there are many near by government offices with canteen and small eating places. Chhole Bhature, Chhole Kulche, Paneer Pakoda, Patiies are all easily available. But I get biscuits and tea in office. For anything else, I eat outside office.
A lot of things particularly hot samosas but since I don't prefer eating outside food I drink tea which gives me enough energy to pass the day smoothly...
In my college days we never have to go canteen but if all have to go we use to drink soft drinks and sometime Aloo Samosa. In office tea and water are famous. :)