Nobody is laughing at the .22, itself. But this is the equivalent of a million dollar judgement for spilling hot coffee. (nobody said the lady didn't get a nasty burn)
As for calling it a "sniper rifle," only if you don't know what a "sniper" is...
That silenced, scoped, .22s have been deployed as "special purpose" weapons by military, assassination, and police units, backed by heavier weapons is similarly not disputed. That's not what happened here.
A legitimate "sniper" would no more carry this weapon in the field than a soldier would carry a tricked out 10/22 for an assault rifle.
A ‘sniper’ according to Websters is “a marksman who shoots at people from a concealed place”
A scoped, silenced .22 calibre rifle is precisely the kind of weapon that would be used by a sniper according to this dictionary definition.