Why would they have used satellite photos when they could just have taken out a subscription to National Geographic and get all the maps they wanted, or bought a Rand McNally road atlas, or a stack of Michelin maps or... well, you get it: there was no shortage of maps of 'the free west' at their disposal. Where satellite photos came into play it would have been to fill in the blanks left by those maps: things which showed up on satellite photos but were missing on recent maps were clearly of interest.
That's not as easy as it sounds, especially in those days.
I'm trying to think of a job or activity that involves scoping out military bases, keeping detailed records of their locations AND getting them home without getting caught at any step in the process. Even today taking a photo of the wrong building in the wrong country can get you into deadly trouble.
Even if your agent is successful, how do you know that he is not misleading you? You now have to risk losing another agent doing the same thing again, just to make sure. Even if your agents don't get caught, they may have come to the attention of and be secretly monitored by the local intelligence services, just to see what they are up to.
Lastly, is confirming the specific location of a base worth losing one or more spies over when knowing the general area is already "good enough"? Your bombers can confirm the location with their eyes (I know of at least one USSR aircraft design with windows on the bottom of the cockpit for exactly this purpose), and your nuclear warhead doesn't really care which side of the road an airport is on.
> Even if your agents don't get caught, they may have come to the attention of and be secretly monitored by the local intelligence services, just to see what they are up to.
Or your agent may have been "turned" by the opposition and they're feeding incorrect information back to you.
