i can be both actually, it just depends on how well i know the person, if your a stranger than 'like a good neighbor, stay over there' although if i know the person and know that there is no ill intent in it than ill happily give you a hug/high five/fist bump. I almost never turn down a hug though unless:
1.) your a stranger
2.) I feel trapped
3.) I feel uncomfortable
4.) you come up behind me and do it (Super close friends and immediate family are the only people who have my permission to do this, even then my friends still ask anyways)