Lets see...... You are missing at least one long range "varmint gun", one intermediate range, one short range. Then there is the calibre issues like small bore, large bore intermediate bore etc etc.. That accounts for six just for one type of shooting..
As Jeff Foxworthy says to his wife who questions his reason for buying another gun... "Honey I own a short range weasel gun, I do need that long range weasel gun".
Or as my daughter often opines "Daddy, a bear collector can never have too many bears"