I feel sad for anybody that dies alone. However, I don't feel responsible for it, why should 'someone who served' be treated more favourably than say - a nurse or a doctor, or even a shop assistant?
While I see your point you are also missing the main point, he was a serviceman and as such he was one of us, therefore if possible it would be nice for any ex service personnel or current service personnel to be present to say, hey mate, you may have gone alone, but you know what, you are not forgotten. It's sort of a cadre thing.
Likewise for Nurses or Doctors or Shop Assistants etc, one hopes there is a website devoted to those occupations and that they are saying hey, Florence Nightingale has died, how about a few of us gathering to see her off...