How can you mess with desperate unemployed people like this

So I've been called to drop off cv and copy of certified ID at the civic then the following day I should go to the civic again at 10 went and waited for 2hrs with no one pitching to conduct the interview was called again on Saturday to setup another app for Monday at 2 at the multi purpose centre, went there with lots of other candidates also that's been there since 12:30 only to be told they we're there this morning and won't be coming out again we should come back tomorrow morning instead!!! How can they be so unprofessional not informing anyone that they canceling saying its impossible to inform 300+ pple of cancelation I mean you can atleast attempt but having pple risking their lives in a community like ours to sit in the wet and cold not nice