Having read through this thread and doing some research online its worth pointing out some of the below :-
Personally - it annoys me when anything is thrown, its not funny, it disrupts the game and puts people in danger - I'd happily "grass" if I knew who did it - because one day it could be someone I know who gets hurt.
People are getting jailed and banned
In November 2013 a Manchester United fan that set off a smoke bomb during their clash with West Bromwich Albion - Sir Alex Ferguson's last game in charge was given a two month jail term (suspended for 12 months) and banned from any football grounds for three years.
In February 2013 two Chelsea fans were jailed for 28 days and given six year football banning orders for taking smoke bombs into the Liberty Stadium for a match versus Swansea City. Their appeal for the sentence was thrown out.
In January 2013 an 18 year old Exeter City fan was jailed for two months and given a six year banning order for attempting to take a smoke bomb into Torquay United v Exeter City.
In August 2012 an Oxford United fan was jailed for two months and given a six year banning order for taking a smoke bomb into Home Park for a match versus Plymouth Argyle.
Recent examples of injuries caused by pyrotechnics at English football grounds
Leeds United v Shrewsbury Town, 11 August 2012 two supporters were injured, one requiring hospital treatment, when an industrial firework was ignited and thrown in the away supporters toilet.
Coventry City v Walsall, 8 December 2012 - a flare was discharged by the Walsall supporters. A steward placed his foot on the device to prevent further smoke escaping, however the sole of his shoe melted causing injury.
Leicester City v Sheffield Wednesday, 9 March 2013 - a female supporter received treatment for burns to her leg from one of the smoke bombs thrown between supporters.
Bolton Wanderers v Huddersfield Town, 2 April 2013 - Bolton supporters ignited a flare and an 18 year old youth was treated for burns picking it up.
West Bromwich Albion v Newcastle United, 20 April 2013 fans were treated for shrapnel wounds following the setting off of thunder flashes. Debris passed through jeans and caused cuts to legs.
Wigan Athletic v Aston Villa, May 2013 - a 15-year-old boy suffered lung damage from a smoke bomb thrown during the game. The boy needed hospital treatment, while two women aged 22 and 24, also required attention for the effects of the device.
Liverpool v Everton, May 2013 an eight year Everton fan was hit by a smoke bomb thrown by fans in the away end. He was treated for a burn on his neck on his first visit to a Merseyside derby.
Aston Villa v Tottenham Hotspur on 20 October 2013 - an assistant referee was struck by a lit smoke canister thrown from the stand.