As far as the SRM is concerned, I find it very much like reading outdated english translations of the Sri Guru Granth Sahib Ji. I personally feel the SRM does more damage than good. Anything that bridges the chasm between Creator and man, that comes from man is always going to be suspect.
When I was younger, I was the only child that was not amritdhari. I recall one of my cousins spitting out a sandwich bite, as I was not 'baptised'. I therefore set my heart on being amritdhari, my dream was to go to Amritsar and be complete when I was due to go to India aged 15. My request was refused, and in hindsight, I am grateful, I would have turned into the very amritdhari Sikh that I now pity. The one that knows all the traditions, all the rituals, all the prayers, but has no idea of the core philosophy.
This type of Sikh is the first to admonish others for doing things 'the wrong way', and has little idea of the power and beauty of the religion. My parents were indeed farsighted.
As for eating food from other people, I am not sure where I stand, as I often share my plate with my dog.