Why do people argue that getting minimum wage to $15 will cause inflation?

I find it very hard to believe that people think that the poor, homeless, and people in the service industry are going to cause massive inflation and eventually lead to another recession? I just do not understand the argument. The wealthy in the US do not trickle down their money, so giving people who make minimum wage more money will be used in a very efficient manner here. So, again I ask, why do people think that this is a bad thing?