We did get burnt. It was just seen as a totally normal thing! People would say "You've caught the sun" and really bad sunburns were seen as something to laugh at 
We did wear sun cream when I was a child (which we called "sun tan lotion" even though it was SPF) but as a child I didn't have the mentality to avoid ever getting sunburnt at all. We would basically put sun cream on if we were going to be out for a long time in the middle of the day but I don't remember ever reapplying it, and we wouldn't wear it for school and stuff, like I do for my DC. One bottle used to last us literally years, to the point the SPF had probably totally expired by the end of it. I think we probably only ever had 3 bottles throughout my entire childhood 
We had after sun/aloe vera gel to put on sunburn to soothe it, and used this regularly. I am absolutely horrified and really cross at myself if I get sunburnt now and would be upset if the DC got burnt (I think unfortunately DS1 probably did get burnt a couple of times because I was more lax when he was younger).
And this was the 90s. I wasn't born in the 70s.
How do you not remember this?
Are you v young, or do you have a skin type which doesn't burn as easily? (I am very pale with ginger genes and have never tanned in my life).
I understood that the reason we are much more hot on sun protection now is because in the past, sunburn was seen as a temporary discomfort (so we'd only bother to try and prevent very bad sunburn) whereas now we recognise that even a "mild" sunburn contributes towards a raised chance of skin cancer in the future. I don't remember thinking about skin cancer in terms of sun protection as a child. Whether that's because it wasn't explained to me or whether it was that the general public weren't really aware of this link I don't know. I knew about the link between smoking and cancer, so I wasn't totally oblivious to cancer risks.