Tim Howard really is flavour of the month in the USA at the moment. Calls from the president and wikipedia hackings have been standard fare since his heroics against Belgium. When you play well in the World Cup knockout rounds you're going to expect a little bit of added attention. When you do it while playing for the US, you should probably expect a lot of attention.
Howard has always come across as quite an affable kind of guy. So when he was greeted at the airport by a bit of welcome party, he seemed happy to pose for pictures and shake some hands. However, he was less happy when one fan attempted to get overly familiar.
Tim Howard definitely prefers when you play it cool.