It's not that Arsenal is fining goalkeeper Wojciech Szczesny that's so notable. It's why they're fining him.
After a New Years Day match against Southampton, in which he shipped two goals thanks to poor positioning, Szczesny was apparently feeling a little down on himself. In order to help cheer himself up, he decided to smoke a cigarette. In the dressing room shower. Like you do.
Szczesny was caught in that odd position by a team staffer and slapped with a £20,000 pound fine, making that perhaps the most expensive cigarette in history. He was also left out of Arsenal's weekend FA Cup match against Hull City, though that's almost certainly unrelated as Arsene Wenger was always likely to play David Ospina in cup matches anyways.
Wenger has been very outspoken about players smoking in the past, disciplining and publicly berating Jack Wilshere for smoking out at clubs after matches. Ditto one-time Arsenal captain William Gallas. If Wenger was that upset about players smoking when out on their own time, one can't imagine he was too thrilled to find out that his goalkeeper was smoking in the same shower all his players use after matches.
Arsenal certainly don't do "boring," do they?