People have been calling the shooting as hoaxes for a long time, but there is usually very little evidence to support such claims. The people who propagate these theories the most are the pro-gun Americans trying to show that Obama's administration is enacting these false flag attacks to create support for gun control laws and eventually take away their guns, a right enshrined in the first Amendment.
It is doubtful that Daesh is directly responsible for this, at the moment it appears to be a spur of the moment attack. But it is pertinent to note that Daesh hasn't been directly linked to most, if any, of these lone wolf attacks. After the attacks happen, they just claim responsibility to get credit. This is the primary goal of terrorist attacks; to get the world's attention.
Regarding, "... just doing it to match the death toll of civilians killed in Iraq, Syria. Lives paid with lives"; it would appear from the point-of-view of an outsider that this statement in some small limited way is trying to justify what Daesh does. Although, I do believe from a naturalistic/secular point-of-view it is expected from a group to inflict losses on their enemies in an identical fashion as they believe have been inflicted upon them; from an Islamic point-of-view it is absolutely disgusting, repulsive and revolting. Additionally, from what I've read, the primary focus of Daesh from these high impact attacks is to polarise the world so that non-Muslims are filled with hatred against the Muslims and when Muslims get persecuted they leave their homes and join-up with Daesh. A fundamental feature of their doctrine that they try to inculcate into their followers is that the time of a final "believer Vs. disbeliever" confrontation has come very near and they are the ones who are going to fight this final battle on behalf of the Muslims.
