There's nothing particularly unusual about idiotic acts at concerts, unfortunately, & Liverpool has seen more than its fair share of those (the Beastie Boys at the Royal Court in 87 immediately springs to mind).
However, the object thrown at Morrissey at the Echo Arena yesterday evening (conflicting reports describe it as either a bottle or a glass), resulting in the abrupt & premature end of the concert (http://www.guardian.co.uk/music/2009/nov/08/morrissey-storms-off-liverpool & http://news.bbc.co.uk/1/hi/england/merseyside/8349102.stm ) is indicative of an all-too common pattern at that venue; several incidents have occurred there with different acts & it seems to date from the venue's inception (http://condensedthoughts.blogspot.com/2008/07/brand-awareness.html ).
The Arena appears to be the only major indoor venue which allows the sale of alcohol during concerts. Its level of security & stewarding also leaves more than something to be desired; a friend of mine went to see Bob Dylan at the venue earlier this year & expressed both his amazement & exasperation at the ease with which people already the worse for wear could return to the bar time after time.
The management of the Arena have offered a limp statement, citing their faith in CCTV to identify the culprit. However, they, too, should accept culpability for last night's incident, in that they preside over a venue in which the standard rules of procedure are blithely suspended.
And what of the venue's sponsors, our old, beseiged friends on Oldham Hall Street? Well, to their credit, they did report the event on their website yesterday evening (some might say they had no option). However, it is telling that the guiding, emaciated hand of desperate PR ensured that both the news report & the follow-up story featuring reaction quotes appeared to imply that Morrissey was a bit of a wimp for not tolerating the odd missile or two (http://www.liverpoolecho.co.uk/liverpool-news/local-news/2009/11/08/former-smiths-frontman-morrissey-leaves-liverpool-s-echo-arena-stage-after-being-hit-by-drink-thrown-from-crowd-100252-25116788/ & http://www.liverpoolecho.co.uk/liverpool-news/local-news/2009/11/08/morrissey-storms-off-liverpool-s-echo-arena-stage-after-being-hit-by-drink-fans-reactions-100252-25116893/ ).
Memo to the remaining hacks on Oldham Hall Street: it's called zero tolerance, it's of a piece with your manufactured "campaigns" & "crusades"; think ASBOs, guys, then you might get the message.