There were a lot of bands with crap PAs back in those days--mostly because there weren't any good off the shelf PAs, and partly because, even if there had been, they would have been too expensive--When I was in high school and college it was pretty standard for garage bands to build their own PA speaker columns, and not uncommon for the PA amp to be built from a kit by someone in the band and their brother--

Of course, that home made stuff evolved very quickly into the massive custom engineered sound systems that were everywhere by the end of the 60's--many of which didn't sound much better than the garage stuff--

I just was reading about John Fogarty, who apparently developed his singing style because, early on, his band worked without a PA--