Why don't liberals like Ted Turner give all their charitable contributions to the government

Now... I do admire Ted for giving of his great wealth... but I noticed he gives it to charities of his choosing. For example... the Bill Gates foundation. Why doesn't he just give it all to the government? Doesn't the government know what is best and needed of those funds. You know... because conservative are labeled as being inhumane and selfish because we choose to give through charity rather than government. It is fact the conservatives give more through charity. (look the study up yourself... don't beg me to research for you) But libs claim higher taxes to bring more into the government to subsidise special interest programs such as Univ. Health Care.... so why has Ted promised BILLIONS to Gates? Why not the government?