understandably they where expecting Russian air superiority so they prepared for urban warfare hence the guns (specifically for the territorial defense army and its auxiliaries which is akin to a wartime neighborhood watch). Against the odds Russia never achieved air superiority so ye in hindsight it was wasteful but not a pr move (and pr that bolsters the moral wouldnt be bad either). also these neighborhood watch type conscripts didnt confront the russian army head to head. but due to the russian army circumventing smaller towns (to not bind resources and slow their advance) the territorial defense would come out and pick off supplies and wear down down moral at night.