I don't think any player should get grief, but I do think Welbeck is one of our weaker options. He does always seem to give 100%, so that is a plus.
Giroud is a very important player at Arsenal. He scores goals and more importantly he scores important goals at crucial times. He also offers us different options up front and brings other players into the frame to score goals too. Never given any truck to the grief he's been given by some fans. He's always given 100% and he's a very loyal servant to the club.
Only recently. In Girouds first 3 Seasons he got alot of grief because he seemed to go missing in the bigger games. I cant find the stats but his finishing against the bigger sides was nothing short of dreadful. There were also alot of goal stats floating around.. http://i.imgur.com/K4TQdCu.png He also went missing in numerous important Champions League fixtures. However he seems to be more alot more confident these days and looks like a much better player. But I would say the critiscm of Giroud was somewhat warranted. I like the fact we now have two very different centreforwards. Gonna be hard for teams to deal with two totally different types of attack.