szov, they're probably Bangladeshis that are cooking a variety of Indian dishes from all over, which have been westernised accordingly (such as vindaloo with potato in it).
Jeff, if you don't like too much spice, go for something like a rogan josh or a bhuna if you want to take a step away from butter chicken. If you like spice, a madras is sometimes a good option.
An Indian restaurant near my usual hotel in London also has Bangladeshis cooking (it's pretty good). Might explain why there's no pork in Jeff's restaurant. In Singapore, many South Indian restaurants are operated by Muslims. The vegetarian restaurants (great stuff, btw) are mostly operated by Hindus.