An apostrophe can be used to show possession (as in “a writer’s mistake”) or to indicate that one or more letters have been omitted from a word or phrase (as in “I can’t believe this”). Here, an apostrophe is used to show that the Yahoo! Style writer has no idea when to use an apostrophe:
What letter or letters did she think were missing from ole? Was that short for oleo? Oleander? Maybe she meant olé. Or maybe she meant a shortening of old and should have written ol’.