AviK, the point is to accommodate so everyone can eat. your examples are weak ones:
If there is a patient who is machmir on eating gebrochts (?), he can take a paper cup, fill it with water and dip his matzo in it without compromising any other patient’s ability to eat.
And sefardim might like to eat rice on pesach (not all sefardim by the way, and some who would don’t because they find it to burdensome to check it 7 (or is it 10) times) but they do not have a mitzva to eat it and get no aveira if they don’t.
Would you have a problem with the army or hospital enforcing a nut-free menu because some are allergic? but what about those people who really enjoy their PB&J sandwich? Is it right to force someone’s food sensitivities on them?