Seriously, who WANTS to go to a funeral? You go out of obligation, out of respect, out of friendship. There are as many reasons for going as not going.
4 went, the other 21 ( as you said) had their reasons for not going. We understand that. We also understand that everybody's actions are judged. You don't go to Aunt Martha's service, family members will have an opinion on it and maybe you will hear about it if you dare show up for the family Christmas. As a public figure, the judgement is on a larger scale and it is public.