Hi, or it is just different between AE and BE, which is what my dictionary defines.Many advertisements have fine print. Fine print refers not only to the size but the fact that there are details included in that print. The fine print could actually be in a large font and still be called fine print.
Credit card advertisements, cell phone ads, club membership - such as book clubs, music clubs, flower clubs, etc. - are just a few examples of ads that have fine print. The fine details do indeed include legal information, but the topic isn't necessarily legal paperwork. Television and radio advertisements put the fine 'print' in a softer and faster speech.